Choosing a shop, getting a second opinion and handling a repair that went wrong
Tell a dealer, an independent shop and a chain apart, read what ASE and AAA marks certify, get a second opinion on the same facts, and take a repair that went wrong from the counter to the state agency in writing.
- Start here: the essentials
- Dealer, independent shop or chain
- Certifications, registration and a first small job
- Second opinions and second estimates
- The repair warranty and comebacks
- When a repair goes wrong: from the counter to the state
- See it: Priya's shop and Gloria's question
- Practice: your shop and your state's route
- Your car
- Check your work
- Knowledge check and scenario
Start here Essentials
For a first pass, this chapter asks you to write down who services your car and what its marks mean, and to know the route for a repair that goes wrong before you need it. Everything marked Go deeper is optional.
- Write down the shop's name, registration number where your state has one, phone and labor rate on the car facts sheet (kinds of shop).
- Check what certifications the shop shows and what each one means. Most cover a technician, not the shop (certifications).
- For a large or doubtful repair, get a second written estimate on the same work (second opinions).
- If a repair went wrong, talk to the manager with the invoice, then write to the shop, then go to your state's agency (when a repair goes wrong).
Minimum time: about 30 minutes, with one invoice from the shop in hand. Done when: the car facts sheet has the shop's details, and any open problem has a written complaint with a date on the service log.
Dealer, independent shop or chain Understand
Most car owners choose among a few kinds of repair business. The kinds differ in what work they can do for free under a warranty, not in whether the law covers them: Florida's repair act, for one, applies to dealers, garages, service stations, self-employed mechanics, and body, brake, muffler, transmission, mobile and glass shops alike (Florida Department of Agriculture and Consumer Services, Motor Vehicle Repair).
- A dealer service department is the shop at a dealership that sells a carmaker's vehicles under the carmaker's franchise.
- An independent shop is a repair business not tied to a carmaker. It may work on many makes or specialize in a few.
- A chain is a company with many locations under one name, including quick-lube shops for oil changes and fluid services, and tire, brake and muffler chains.
- A specialist does one kind of work, such as transmissions, glass or body repair. Some shops only diagnose and do not repair; the FTC says such a shop "may be able to give you an objective opinion" (FTC, Auto Repair Basics).
What matters first is the warranty. The FTC's warranty page says you do not have to use the dealer for repairs or maintenance to keep your warranty, and that it is illegal for a dealer to deny warranty coverage because routine work was done elsewhere. It also says that when a warranty provides free work or free parts, the carmaker or dealer can require you to use the facilities it chooses (FTC, Auto Warranties and Auto Service Contracts).
| The work | Where it can be done | Keep |
|---|---|---|
| Maintenance and repairs you pay for, while the car is under a factory warranty | Any shop, a dealer or not, or you yourself | Receipts for every service, on the service log; the FTC says a claim may be denied without records |
| A repair the factory or emissions warranty pays for | The facilities the warrantor names | The warranty booklet's terms and end dates, on car facts |
| A recall repair | See Recalls, warranties and service contracts | The recall check, on the recalls sheet |
| Anything after the warranty ends | Any shop | The same records; they help at sale and on the next diagnosis |
Recalls, warranties and service contracts explains the federal rule behind the first row and what a carmaker can still deny. Ask the authority
Beyond warranty work, which kind suits you is your choice. Price is one factor: AAA's labor-rate article says dealers usually charge more than independent shops (AAA, Average Mechanic Labor Rate 2026), and each shop's posted rate is the number to compare. Distance, hours, whether the shop works on your make often, and whether it explains its work in a way you can follow are others. Preference We do not rate shops or chains, and no kind of shop is the right one for every car. For a hybrid or electric car, ask whether the technicians who would work on it are trained on high-voltage systems; Hybrids and electric cars explains why. Ask the authority
Certifications, registration and a first small job
Shops display marks: signs, decals and certificates on the wall. Each mark certifies something specific, and most certify a person rather than the business. Read each for what it requires.
| Mark | Who it covers | What it requires | What the source does not say |
|---|---|---|---|
| ASE certification | One technician, in one area per test | At least 2 years of qualified work experience and a passed test for each certification; a retest every 5 years | That the shop as a whole is certified; ASE says it "certifies technicians, not businesses" |
| ASE C1 (service consultant) | One service advisor | A passed C1 test and 2 years of work experience in service writing; a retest every 5 years | That a shop has to employ one |
| ASE Blue Seal of Excellence | A shop | At least 75 percent of its technicians who diagnose and repair are ASE certified, with each service area covered by at least one; eligibility reviewed yearly | That ASE inspects the shop's pricing or workmanship |
| AAA Approved Auto Repair | A shop in AAA's network | Inspected by AAA; technicians ASE certified or factory trained | That non-members get the member terms |
| State registration | A shop, in states that register them | Set by each state | Anything about quality, unless the state says so |
Sources: ASE, Resources for Drivers; ASE, C1 test; ASE, Blue Seal of Excellence; AAA Approved Auto Repair.
ASE certification comes from the National Institute for Automotive Service Excellence, a certification body that tests individual technicians in separate areas; its technician series runs A1 through A9 for cars. So an ASE sign in the window tells you that someone there holds an ASE certification; it does not say who, or in what. ASE's own advice is to ask to see a technician's credentials. Ask which technicians are certified in the area your repair needs, such as brakes or electrical. The FTC adds that ASE certification is no assurance of good or honest work. Convention
AAA Approved Auto Repair is a network of shops that AAA, a membership organization, has inspected. Its terms are for AAA members who show a valid card at the time of service; they are in the Go deeper note below. Product-specific
State registration. Some states register repair shops, and where they do, the number is a way to find the shop's record and file a complaint. California's BAR says a final invoice there carries the shop's license number (BAR, Maintenance and repairs). Florida's invoice statute requires the shop's state registration number (Florida Statutes 559.911). New York's registered shops display a green and white sign that reads "Registered State of New York Motor Vehicle Repair Shop" (New York DMV). Michigan's Department of State registers repair facilities (Michigan Department of State). These are examples; whether your state registers shops is a question for its consumer agency. Write the number, if there is one, on car facts. Ask the authority
ASE, Blue Seal and AAA terms in detail Go deeper
ASE. The C1 test for service consultants has 50 scored questions on communications, customer and internal relations, vehicle systems knowledge, sales skills and shop operations, and runs 75 minutes; the recertification test is 25 questions in 30 minutes (ASE, C1). ASE's driver page also quotes marketing figures for certified technicians drawn from a chain's data and from self-reported professionals; we do not repeat them, because they are promotional.
Blue Seal. Beyond the 75 percent rule, ASE's program page says service consultants need C1 and collision estimators need B6, and that a shop pays $235 to apply and $65 a year (ASE, Blue Seal). The shop pays for the recognition, which is worth knowing when you read the sign.
AAA Approved Auto Repair. AAA's page lists over 7,000 approved facilities in North America and these benefits for members: written estimates for all work, a final bill that will not exceed the estimate by more than 10 percent without approval, a 24-month or 24,000-mile repair warranty, a labor discount of at least 10 percent (limited to $75 in some areas), and AAA mediation of disputes (AAA Approved Auto Repair). The page does not say non-members get these terms. AAA has an interest in its own network: its 2016 survey release, which advises trying a shop on a minor job, also promotes the program (AAA newsroom, December 2016).
A first small job to judge a shop
A sign says what someone passed; a visit shows how a shop works. Our method is to try a shop on a small, scheduled job before you need it for a large one, and to notice a few things you can see. This manual's convention AAA's 2016 release gives similar advice: find a shop before you need one and try it on a minor job, such as an oil change. The things to notice come from the tasks ASE tests service advisors on and from the paperwork rules in Reading a repair estimate.
| Notice | Where it shows |
|---|---|
| Your concern written down in your words | The work order; ASE's C1 guide lists discussing and documenting the customer's concern as a task |
| A written estimate before work, and a call before anything more | The estimate, and whether a call came |
| Recommendations that come with what was seen: a measurement, a photo or the part | The inspection or list; Discussing recommendations |
| Your questions answered in terms you can follow | The conversation; the C1 guide lists explaining inspection results and estimates |
| An invoice that matches what you approved, with declined work listed | The invoice |
| Ready when promised, or a call if not | Pickup |
The C1 tasks are in the ASE C1 study guide (PDF). Write what you noticed in the service log's notes for that visit. One visit is a small sample, and a shop can do well on an oil change and differently on a complex repair; the table records what you saw, not a verdict on the shop.
Second opinions and second estimates
There are two different requests, and they need different facts.
- A second opinion asks another shop what is wrong, or whether work is needed. It is a diagnosis.
- A second estimate asks another shop what the same work costs. It is a price, and it compares only when the work, the part type and the warranty match (Reading a repair estimate).
When to ask. California's consumer guide says not to feel pressured to agree to any service, to ask why a service is needed, to decline until you can research it, and to get a second opinion (BAR, A Consumer's Guide to Auto Repair (PDF)). Cases where it fits: a large repair, a diagnosis you doubt, or a recommendation that is not in your maker's schedule (Discussing recommendations). When a technician says a part is unsafe, that is a reason to have it checked before you drive on it, by that shop or another; it is not a reason to skip the check. Ask the authority
How to ask for a second opinion. Give the second shop the facts, and leave out the first shop's verdict and price, so the second answer is its own. This manual's convention
- The symptoms, written by what, where, when and how often, from your symptom log (Sounds, smells, leaks and feel).
- Any warning light and any code read, with the date.
- The mileage and recent work, from the service log.
- A request for a written diagnosis and a written estimate.
If you want both shops to measure the same part, such as brake pad thickness, ask the second shop to measure it, and compare the two numbers afterward. Expect a diagnosis fee at the second shop: the FTC says many shops charge for diagnostic time, and suggests asking whether there is a charge if the work goes elsewhere. Ask the first shop the same question before it starts (Reading a repair estimate).
How to ask for a second estimate. Hand over the first shop's written list, line by line, with the part type and warranty you want quoted, and ask for a written quote on the same specification. Put both on the estimates sheet.
If the car is already apart. Moving a car that is partly disassembled costs money and time. Two example states have rules for it. In Florida, when a shop says the repair will run over the estimate, you may cancel; the shop puts the car back together unless you waive that or it would be unsafe, and may charge for the tear-down and reassembly only if the estimate disclosed those charges (Florida Statutes 559.909). In California, a tear-down estimate states the cost of putting the car back together (BAR, Write It Right). Wherever you are, ask what reassembly costs before you decide.
The repair warranty and comebacks
A repair warranty is the shop's own promise about its work and the parts it installed, separate from the carmaker's warranty on the car. It is not automatic. The FTC says "There is no 'standard warranty' on repairs." California's consumer guide says a shop there is not required by law to guarantee its work, and that a shop that does should state the terms, how long they last, what is excluded, whether the coverage is prorated and whether it transfers to a later owner. New York's DMV says the same about shops in that state, and that warranty terms, if any, go on the invoice. Florida's statutes put any guarantee's terms on the estimate and the invoice. Ask the authority
Ask before you authorize, and check the invoice afterward:
- How long, in months and in miles?
- Parts only, or parts and labor? The FTC notes that a remanufactured part's warranty often covers the part but not the labor to replace it.
- What voids it, and what is excluded?
- Does it transfer if you sell the car?
Write the answer in the service log's repair warranty column for that job. That column is what you check first when something goes wrong.
Comebacks. A comeback is a car that returns with the same problem after a repair. ASE's C1 guide lists addressing repeat repairs and comebacks as a shop operations task, so a shop should expect to hear about one. If a problem returns, go back to the same shop first, with the invoice, and describe the symptom the way you did the first time. Massachusetts' consumer guide says work not done to the trade's standards is redone there at no charge; that is one state's rule, and the repair warranty's terms are the place to start elsewhere (Massachusetts Consumer Guide: Mechanics of Auto Repair). Log the return visit on the service log, with the original visit's date in the concern.
When a repair goes wrong: from the counter to the state
A repair can go wrong in several ways: a bill over what you authorized, work you did not approve, a problem that came back, or a part that was charged and not installed. The routes agencies publish run in the same order, from the shop outward. The FTC says to start with the shop's manager or owner, then go to the state attorney general or a local consumer agency. Michigan's Department of State says to try the owner or manager first (Michigan Department of State, File a complaint).
- Talk to the manager or owner, with the invoice and your written authorization. Say what you approved, what happened, and what you ask for: an amount refunded, the work redone, a part shown. Note the date, the name and the answer.
- Put it in writing to the shop. One page: the car, the dates, the invoice number, what you authorized (attach it), what went wrong, what you ask for, and a date to reply by. Keep a copy, and log the date on the service log. This manual's convention Massachusetts' consumer guide describes a formal version, a 30-day demand letter under the state's consumer protection law; other states have their own forms, so ask your state's agency.
- Go to your state's agency or attorney general. USAGov sends complaints about repair shops to your state's consumer protection office, and complaints about a car's warranty to your state's attorney general (USAGov, Where to file a complaint about your car). Some states have an office just for repair shops. The examples below show what the process looks like.
| State (example) | Where to file | What the agency says about the process |
|---|---|---|
| California | Bureau of Automotive Repair | A representative contacts you within 7 to 10 business days; mediation may produce a refund, a bill adjustment or a free repair. A complaint does not mean the shop broke the law or that enforcement follows. Repairs done outside California are out of scope. |
| New York | DMV, on form VS-35 | File within 90 days or 3,000 miles of the repair, whichever comes first; no anonymous complaints. About half are resolved through mediation. Restitution is limited to the overcharge or the cost of a proper repair. The DMV does not resolve carmaker or third-party warranty disputes. |
| Michigan | Department of State, online or on form SOS-197 | Try the owner or manager first. You may file even if you did not have the repairs done, for a claim of unneeded repairs. Its authority is limited to the state's vehicle code and repair act. |
| Florida | Department of Agriculture and Consumer Services | An online form or the 1-800-HELP-FLA line. |
| Washington | Attorney General | Lists the office's mediation, arbitration or mediation services, small claims court and an attorney as options. |
| Massachusetts | Consumer guide | Mediation through local consumer programs, and the 30-day demand letter. |
| Your state | USAGov, State consumer protection offices | Look for the office's auto repair page and any time limit, and write both down. |
New York's 90-day or 3,000-mile limit shows why the order matters: the time to file can run while you are still talking to the shop. Check your own state's limit when the problem starts, not after the shop says no. Ask the authority
If you paid by credit card
The Fair Credit Billing Act lets a credit card holder raise some disputes with the card issuer. For a dispute about the quality of goods or services, the statute sets three conditions: you made a good-faith attempt to resolve the problem with the shop; the purchase was more than $50; and it took place in the same state as your mailing address or within 100 miles of it. The amount and distance conditions do not apply when the shop is the card issuer or is controlled by it, among other exceptions (15 U.S.C. 1666i, Cornell LII). The FTC's page on disputing charges describes the steps, including a written dispute that reaches the issuer within 60 days after the first bill with the error was sent (FTC, Using Credit Cards and Disputing Charges). That page gives a different dollar figure for quality disputes than the statute does; we cite the statute. Debit cards are not covered by these sources. Ask your card issuer which kind of dispute your problem is, and how it wants it filed. Ask the authority
Small claims court
Small claims court is a state court for disputes under a dollar limit, with simpler procedures. The FTC says you don't need an attorney there. Washington's Attorney General notes that in small claims you can only sue for money: a court can award an amount, not a repaired car (Washington Attorney General, Auto Repair). Limits, fees and procedures vary by state, and we did not research them. It is something to ask your county's court clerk or your state's agency about. Ask the authority
Liens and storage: why a disputed bill should not sit
A mechanic's lien (some states say possessory lien or garage keeper's lien) is a shop's legal claim on a car for unpaid repair charges. Where a state allows it, the shop can keep the car until it is paid, and storage charges can be added while it waits. Both are reasons to resolve a disputed bill quickly. The rules differ by state:
| State (example) | What the source says |
|---|---|
| Washington | A shop may keep the car until paid if the charges are within 110 percent of the authorized estimate. It may not hold the car if it failed to return parts you asked for, give an estimate, get your authorization or post the required customer rights sign (Attorney General). |
| Florida | It is unlawful to keep a car because the customer refuses to pay unauthorized or excess charges (559.909). If a shop holds the car over disputed charges, the state agency describes filing a bond with the clerk of the circuit court for the bill plus storage; the clerk issues a release, and the shop has 60 days to sue on the bond (FDACS). The estimate discloses any daily storage charge, with none for 3 working days after you are told the work is done (559.905). |
| Michigan | A registered facility can keep an unpaid vehicle and file a lien with the Department of State (Department of State). |
| California | A shop may hold a lien sale for unpaid authorized charges only if it met the invoice requirements (BAR, Write It Right). |
| New York | You may inspect the car before you pay, but not take it without paying (DMV). |
| Massachusetts | The shop tells you about storage charges before you authorize work (consumer guide). |
Two of these rules turn on paperwork: Washington's on the estimate and authorization, California's on the invoice. That is one more reason to keep the written estimate, your authorization and the invoice together on the service log and in the file. Whether to pay a disputed amount and contest it afterward, or to leave the car, is a decision with legal consequences that differ by state. Ask your state's agency before you choose.
This chapter gives the routes agencies publish, as examples, and the questions to ask. It gives no legal advice. Whether a charge was lawful, whether a shop may keep your car, whether to pay and dispute later, and whether a card dispute or a court case fits your facts are questions for your state's consumer agency or attorney general and, for a large sum, a lien or a car the shop is holding, a lawyer. The state examples are not a summary of your state's law. The manual does not rate shops, recommend chains or say that any shop did wrong. Ask the authority
BBB AUTO LINE: what it covers
BBB AUTO LINE, run by BBB National Programs, handles vehicle warranty, lemon law and class action disputes with carmakers that take part in it. It is free to owners of participating makers, which fund it. Eligibility depends on the maker taking part, the problem being covered by the warranty, and the state, the car's age and its mileage. A case goes to mediation and then arbitration; the decision is not binding on the owner, and binds the maker if the owner accepts it (BBB National Programs, How BBB AUTO LINE Works). Its page describes disputes with carmakers under their warranties. It does not describe disputes with repair shops, so a bill from an independent shop goes by the state routes above. Warranty and lemon-law questions are in Recalls, warranties and service contracts.
Two terms from the dispute routes
Mediation is a process in which a neutral person helps both sides reach their own agreement. Arbitration is a process in which a neutral person hears both sides and decides; whether the decision binds you depends on the program and what you agreed to. California's BAR, New York's DMV and Washington's Attorney General all describe mediation; BBB AUTO LINE and Washington's list describe arbitration.
See it: Priya's shop and Gloria's question See it
Priya Raman is a fictional person; every fact about her, her car and her shops is invented for this manual. She is 34 and uses she/her. Her 2017 gasoline compact sedan, out of warranty, has 98,400 miles. She has used the same independent shop twice.
Known: the shop's labor rate is $140 an hour. On this visit it sent the inspection and the estimate in writing, by text, with the front pads measured at 3 mm and a photo. She has two earlier visits there to judge it by, the way the first small job table describes. The shop's repair warranty on the brake fluid and filter work is on her invoice: 12 months or 12,000 miles (fictional). For the front tires she got a second written estimate from Shop B: same size and load, $260 with road hazard coverage, against her shop's $268 without it.
Assumed: that her state registers shops. Her shop's invoice settles it: a registration number printed on it, or none.
Open: the registration number (the invoice or the sign on the wall); which technicians hold ASE certification, and in what (she asks at the counter); and whether the two tire quotes are the same tire (each shop names it in writing).
On car facts, Priya writes the shop's name, phone, $140 an hour, and the registration number or "none on invoice." The car is out of warranty, so where it is serviced has no warranty consequence; recalls still apply (Recalls, warranties and service contracts). Nothing has gone wrong, so the dispute route is a line she writes down for later: her state's consumer protection office, found through USAGov's directory, and its time limit, if it has one.
Gloria Hernández is a fictional person; every fact about her and her car is invented for this manual. She is 71 and uses she/her. Her 2011 gasoline midsize sedan has 162,000 miles. Her son, Luis Hernández (he/him), helps by phone. The shop's diagnosis, $140 for one hour, found a failed ignition coil on one cylinder, and the repair estimate is $310. The shop marks the catalytic converter "watch" until a test after the repair and a few days of driving. Her VIN shows no open recalls; Recalls, warranties and service contracts notes that the search leaves out recalls more than 15 years old.
Gloria and Luis ask whether to repair the car or replace it. The manual gives no rule for that. It gives the questions they weigh:
- What does this repair fix, and what is still open? The coil, under the assumption that it is the whole fault; the converter, until its test.
- What else is on the shop's list, or due on her schedule in the next year, and what would each cost? Her recommendations and schedule sheets hold the answers.
- What has the car needed over the past year? Her service log shows it.
- Is there rust or collision damage? Consumer Reports says either can make a car structurally unsound; the shop can look and say what it sees.
- Does the car still fit her trips and her safety needs, and how can Luis help with either choice?
- What would a replacement cost her, and how would she pay for it? That is her decision; this manual gives no financial advice.
Known: the diagnosis, the estimate, the recall check. Assumed: that the coil is the whole fault, which is the shop's diagnosis. Open: the converter (settled by the shop's test, logged on the recommendations sheet), the next year's costs (her schedule and the shop's list), and the decision itself, which is Gloria's. Under these assumptions, the question in front of her this week is a $310 repair, plus the diagnosis fee if the shop bills it separately; the converter test settles whether a larger question follows.
One publication's rule. Consumer Reports' 2016 article on deciding whether to buy a new car says to think about cost, safety and connectivity, and gives a rule of thumb: start shopping when a year's repair bills exceed a year's car payments (Consumer Reports, How to Decide If You Need a New Car). It is one publication's rule, dated 2016, and we show it as that. We found no other non-commercial source with a rule, so the questions above are this manual's frame. This manual's convention
- ASE, Resources for Drivers: what ASE certification requires and what it covers.
- California BAR, File a complaint: one state agency's complaint process, scope and what mediation can produce.
- USAGov, Where to file a complaint about your car: which office handles shops, warranties, loans and safety.
- 15 U.S.C. 1666i (Cornell LII): the statute's conditions for a credit card quality dispute.
Practice: your shop and your state's route Practice
Minimum: one shop on the car facts sheet with its name, registration number if your state issues one, phone and labor rate, and your state's complaint office written down. Time: about 30 minutes. Materials: an invoice from the shop, the car facts sheet and the service log (or paper), and a phone or browser.
- Fill in the shop from an invoice. Name, phone, and any registration or license number printed on it. If the labor rate is not on the paperwork, ask for it.
- Read the marks. Note any ASE, Blue Seal or AAA sign, and ask which technicians are certified in the areas your car is likely to need.
- Find your state's route. Open USAGov's directory of state consumer protection offices, find your state's office and its auto repair page, and write down the office, the link and any time limit.
- Write down the repair warranty. From your last invoice, in months and miles, in the service log's repair warranty column.
- If a problem is open, write to the shop. One page, with the dates, the invoice number, what you authorized and what you ask for; log the date on the service log.
Plan a first small job. If you have no shop yet, or want to try another, book a scheduled item from your schedule there and keep the first small job table beside you. Rehearse a second opinion. For the next large estimate, write the symptoms, codes and mileage on one page as you would hand them to a second shop, without the first shop's diagnosis or price.
Your car Your car
Check your work Check your work
Criteria
- Does car facts name your shop, with its phone, labor rate and registration number, or say there is none?
- Can you say what each mark on the shop's wall certifies, and whom?
- Do you know where free warranty work, paid maintenance and recall repairs can be done for your car?
- Is your state's complaint office written down, with any time limit?
- Is the last repair's warranty, in months and miles, on the service log?
- If a problem is open: is there a written complaint to the shop with a date on the service log?
Worked example
Priya's car facts list her independent shop with its phone, $140 an hour and the registration number from her invoice, or "none on invoice." Her service log carries the 12-month or 12,000-mile repair warranty (fictional) for the brake fluid and filters. Her state's consumer protection office is written down with the date she looked it up. It passes. It does not say her shop is a good one or a bad one; it records what she can see and where she would go. Gloria's notes pass on the same terms: the repair-or-replace questions are written out, the open facts carry who settles them, and the decision is left to her.
Common mistakes
- Reading an ASE sign as a shop certification. ASE certifies technicians. Ask who holds which certification.
- Giving the second shop the first shop's verdict. You get a check of the first diagnosis rather than a second one. Give symptoms, codes and mileage.
- Comparing a second estimate on different work. Match the work, the part type and the warranty first.
- Assuming the shop warranties its repair. There is no standard repair warranty. Ask and write down the terms.
- Waiting before filing. A state's time limit can run while you are still talking to the shop. New York's is 90 days or 3,000 miles.
- Letting a disputed bill sit while the car is at the shop. Storage charges and liens make delay costly in some states. Ask your state's agency what applies.
What is still unresolved
Whether a particular shop does good work is something you judge over visits, from what you see; no mark settles it. Whether a charge was lawful, and what to do about a car a shop is holding, are settled by your state's agency or a lawyer. Whether a repair on a warranty should be free, and where it goes, is in Recalls, warranties and service contracts. How to read the estimate and what you authorized is in Reading a repair estimate, and how to keep the papers a dispute depends on is in Your service records.