New-car dealers tend to sell late-model used cars (two- or three-years old) that often carry the remainder of the original factory warranty. Generally, dealer cars are higher quality due to age and their ability to readily make repairs.
Auto superstores have huge lots and scores of cars to sell. CarMax, auto malls, and rental-car sales lots sell numerous brands under the same roof and have their own large-scale reconditioning operations. They also put age, condition, and mileage limits on the cars they’ll sell.
Independent used-car dealerships are apt to handle any car make, and the vehicles can run the gamut from almost-new to junker-in-waiting. Favor the dealerships that have been around for a long time and have a good reputation locally.
Independent mechanics and body shops often have a sideline business selling a few used cars. They may not have a large selection, but it costs them little to fix cars up. That means their prices can be better than those you’ll find at a dealership.
Private owners may sell their cars for less, but there are limits. Businesses that sell cars required to offer some kind of warranty by law and have the expertise to spot problems. Private sellers can’t provide the same security. All the private transactions are assumed to be ‘as-is.’