Performance cars are not good things to buy used. Think of the profile of the average customer for these cars. Do you think a buyer of a new Camaro or Nissan 370Z is interested in comfort, cabin accoutrements or the number of cupholders? Hardly. They're interested in seeing what the car "can do" -- and that means plenty of stress on the engine, suspension and other expensive systems. (By the way, isn't that why you're interested in that type of car, too?) So don't expect a used performance car to have been treated gently.