I've had my share of duds over the years. A missing key fob or balding tires don't exactly qualify as a bad experience when it comes to buying used cars.
Always test drive the car in a quiet dead end street to hear for suspension noises, I once negotiated with a used car dealer to replace worn out struts at a discount. Another time after 2 successive failures on a low mileage CRV (a dead battery, worn out clutch) I made a deal to swap out the lower mileage CRV for a higher mileage Explorer which had less problems.
Mileage is where these used cars suffer sometimes unfair depreciation. A higher mileage one may have been driven 90% highway on great roads whereas the lower mileage one may have been used in bumper to bumper traffic in pot-holed riddled streets by someone who rarely did P.M.
Like the old saying goes once you let the cat out of the bag you never know what'll come up next. And in the end it's all luck.