The person you need to question is yourself, so this is probably going to be the easiest step in the process since you should already know the answers. Figure out what kind of used car you're looking for by examining the reasons you need it, the mileage you expect to put on it, and how long you plan to keep it.
Also take a look at your financial situation. How much money can you afford to spend? This includes the purchase price, as well as how much it's going to cost to keep the car running properly. Think about gas prices, the type of tires the car needs, and how much it costs to repair that model.
Answering these questions will help you determine not only the ideal model for you and your budget, but also the oldest model you're willing to buy, as well as the highest mileage you're willing to accept.
When making a purchase as big as a vehicle, you shouldn't limit yourself to visiting just one dealership or private seller. Sure, it's possible to find your perfect used car at the first place you look, but it's unlikely.
Visit several dealerships in your area and even beyond, if you're willing to travel. Check your local newspaper for advertisements; this is also a great way to find out about special sales that might be going on. Your newspaper's classifieds section is a good source of advertisements placed by private sellers, as is a trading journal.
Unless you're quite experienced under the hood, the tests you'll perform yourself are probably going to be limited to giving the car a test drive and listening for any suspicious clangs, bangs, squeaks, or vibrations.
If this is your situation, take a friend along who has a bit more mechanical experience than you―taking an actual auto mechanic would be ideal, but it's not possible for everyone.
If you're purchasing from a private seller, ask about taking the car to the shop just down the block for a quick inspection. If they veto the idea, start looking elsewhere. An honest seller isn't going to deny you the chance to have the vehicle checked out by a professional.
During the test drive, try to drive in as many different situations as possible. Remember to thoroughly test the brakes, as well.
This might be the lengthiest step in the process. There are several ways to conduct research when buying a used car, and you should use as many of them as you can.
First, talk with the dealer or private seller. Dealers are supposed to notify you of any circumstances such as salvaged titles; however, private sellers often sell the vehicle "as is" and might neglect to bother with the details.
Next, get a vehicle history report. These reports provide thorough information about the vehicle's title and odometer status, as well as any accidents the vehicle was involved in. If the seller provided you with correct information, the vehicle history report will only reinforce it.
And finally, don't underestimate the power of researching through word-of-mouth―it's often the most truthful form of advertisement. Talk with people who have experience with that particular make and model. There are also many websites that provide owners the opportunity to discuss their vehicles; you might want to search for those, as well.