Nothing ruins a day quite like having your trusty car suddenly break down. Being without your car is bad enough, but what can make this situation worse is getting scammed by a mechanic who’s pretending to help fix your vehicle.

While there are many reputable mechanics who do quality work at a fair price, it’s tough to find them. And if you don’t know a good mechanic, you could fall victim to a car repair scam.

Auto repair scam complaints make up the biggest group of consumer complaints. The National Highway Traffic Safety Administration estimates that consumers lose tens of billions of dollars each year due to faulty or unnecessary car repairs.

Don’t let yourself become a victim of scamming. Check out these five common car repair scams so you don’t get taken to the cleaners at the repair shop.

1. Verbal Estimations

This is one of the oldest, easiest scams in the book. You bring your car in, discuss the issues it’s having, and get an estimate from the mechanic. The mechanic offers a very reasonable estimate, and you leave, pleased to hand over your car for repairs.

However, that reasonable estimate can disappear fast. If you leave a repair shop without a written repair estimate, don’t be surprised if the mechanic calls to tell you your car is all set – and the final bill is three or more times what you expected.

It’s always easy for mechanics to find many more things wrong with your car once they begin working on it, so be sure to get exactly what the repairs will be in writing with the estimated price. Make sure there is nothing left blank on your work order that can be filled in later. This will ensure you don’t wind up paying more than the quoted price or for repairs that weren’t necessary.

2. Repairs with Used Parts Instead of New

When you take your car into the shop for any issue, your mechanic will diagnose the problem and let you know what work is needed. That work typically requires a new part or two. However, have you ever asked your mechanic whether they’ll be using new parts to complete the repair?

Most people don’t think twice about it and assume new pars are always used. However, you need to be sure that you’ll actually be getting new parts put on your car and not used parts at new part prices.

Believe it or not, this is a common practice used by dishonest mechanics. They’ll charge customers for new, premium parts even though they’ve installed sub-standard or used parts.

Ask your mechanic to tell you exactly what parts they’re ordering for you and where they’re ordering them from. You can either call the parts place to see what order was called in, or ask your mechanic for any packaging, receipts, and warranty paperwork that came with your new parts for your records.

3. The Ol’ Bait and Switch Repair Scam

You’ll often see repair shops advertising special discounts on specific repair jobs such as an oil change or tune up. These prices, which seem too good to be true, are exactly as they appear. They’re truly too good to be real prices.

Repair shops will use the $50 tune-up deal to get you in the door. But once your car is up on the racks, the mechanic will come out with some news for you. Your car needs other surprising repairs, new parts, and more and more work. And suddenly, your $50 tune-up turns into $350 in repairs.

If you don’t know about this scam, you’re apt to just say okay. After all, your car is already up on the racks and a professional is telling you your car isn’t safe.

Always get a second opinion before agreeing to have any work done. Even if that mechanic gives you a hard time or tries to guilt you into it, firmly tell them to get your car down and that you’re not interested in any service today.

4. Highway Bandits

This is a classic scams: highway robbers generally own or work for service stations you see along the highways, and they prey on unsuspecting motorists.

You pull in to get some gas, maybe put a little air in the tires, and a serviceman walks up and asks if everything is okay. They may seem like someone who wants to help, but these highway robbers have been known to spray oil or drip it under cars, then claim the car has a leak. Some have even punctured tires and cut water hoses or fan belts. These highway robbers will always gear the conversation toward your safety and what might happen if you don’t get your car fixed ASAP. Then, they charge overinflated prices to fix what they broke.

Unless your check engine light has come on or you’ve been experiencing an odd noise or sensation while driving, drive away and get a second opinion. Don’t let random strangers approach or touch your vehicle – let them know you’ll take the car to a trusted mechanic to have what they claim to be an issue checked.

5. Bogus Engine Flushing

Engine flushing is a way to get rid of unwanted sludge that’s built up in the engine over time. If you’ve taken care of your car and gotten oil changes as often as you should, your engine shouldn’t need this service, which can cost upwards of $200. An engine flush shouldn’t be part of a routine maintenance service either, so if they tell you that’s part of the service, walk away.

How to Find an Honest Mechanic

It’s unfortunate that so much detective work is needed to find a reputable mechanic. But the reality is, there are unscrupulous people in all service industries. That’s why it’s best to do your due diligence and protect yourself from these common scams.

The best way to find a good and honest mechanic is to look for them before you need them. When your car has already broken down, you feel desperate. And desperate people are far more easily conned.

If you’ve recently moved to a new town or city, ask people you’ve met or work with for their recommendations. Once you’ve gotten a few names of repair shops, do some background checks to see their history with the Better Business Bureau. Also, make sure they are registered with the state and check to see if the government has any records of complaints against them.

Reza Estakhrian / Getty Images

This article was worked on by a variety of people from the Autoversed team, including freelancers, editors, and/or other full-time employees.