Booking a mobile mechanic is convenient. Someone shows up, fixes your car, and you didn't have to sit in a waiting room for three hours. But the convenience cuts both ways — because it's also easier for unqualified or dishonest operators to present themselves as legitimate.
Ask these five questions before anyone touches your car. A real professional will answer every one of them without hesitation.
1. Are You Licensed to Operate as an Auto Repair Business?
This one catches people off guard. Most drivers assume that if someone is working as a mechanic, they must be licensed. Not necessarily.
Requirements vary by state. Some states require mobile mechanics to hold a business license, an auto repair dealer license, or register with a state oversight body. Others have lighter requirements. But even in states with minimal regulation, asking the question tells you something.
A mechanic who says "I don't need a license, I just work for myself" may technically be right — or they may not know what's required, which is its own red flag. A legitimate operator knows the rules they operate under.
Ask for the license or registration number. Then verify it with your state's licensing authority. Takes five minutes. Worth it.
2. Do You Carry Liability Insurance?
If something goes wrong — your car is damaged during the repair, your driveway is contaminated with oil, or the repair fails and causes an accident — who is responsible?
If the mechanic carries liability insurance, there's coverage. If they don't, you're dealing with this on your own. And don't just take their word for it. Ask to see the certificate of insurance. Any business that carries insurance will have this document readily available.
This isn't about assuming the worst. It's about making sure both parties are protected if something unexpected happens. A mechanic who gets defensive about this question is telling you something.
3. What Is Your Warranty Policy?
Every legitimate repair comes with some form of warranty on parts and labor. The standard in the industry is 12 months or 12,000 miles, but it varies. Some shops and mobile mechanics offer more. Some offer less. What's not acceptable is "no warranty."
Get the warranty terms in writing. Find out what it covers: parts only? Labor too? What's the process if something fails — do they come back to you, or do you have to bring the car somewhere?
A mechanic who won't stand behind their work shouldn't be working on your car.
4. Can I Get a Written Estimate Before You Start?
This is non-negotiable. The answer should always be yes.
A written estimate should include the specific repairs being performed, a breakdown of parts costs, labor hours and rate, and any diagnostic fees. If the mechanic wants to diagnose first and then give you an estimate, that's reasonable — but the diagnostic fee itself should be on the estimate.
If you get a vague verbal number instead of a written document, you have no protection if the bill comes in higher. Most consumer protection laws that cap final bills at a percentage above the estimate only apply if you have a written estimate to begin with.
No estimate in writing, no work on the car.
5. How Do You Source Parts — OEM or Aftermarket?
This question does two things. First, it tells you whether the mechanic is thoughtful about parts quality, which matters for how long the repair lasts. Second, it lets you make an informed choice about what goes into your vehicle.
OEM (Original Equipment Manufacturer) parts are made by or for the vehicle manufacturer. They fit and perform exactly as the factory intended and typically carry better warranties. Aftermarket parts vary widely — some are excellent, some are garbage.
Neither is automatically better in every situation. But you deserve to know which you're getting and why. A mechanic who buys whatever's cheapest without discussing it with you first is putting their margin ahead of your car.
Also: make sure the parts installed match what you're billed for. Charging for OEM and installing aftermarket is fraud — and it happens.
These five questions take about ten minutes. They're the difference between trusting the right person and handing your car to someone who shouldn't have it.
For more on vetting mobile mechanics, see our Avoiding Scams guide. And to find pre-vetted mobile mechanics in your area, check our Find a Mechanic directory.