it also depends on your engine type. V8's and 4 bangers last longer then 6's. As someone who has been around car sales and has a dad who bought and sold cars to dealers, here is some advice. -little advice, go to two different dealers of the same car, get different qoutes and play each dealer off of each other. -be willing to walk away. Go in with a price you are willing to pay(within reason), if they arent willing to get close, stand up, say thank you and walk away, but leave your number, they will call you. -Never and i repeat never buy the after market warranty, undercoating, or the stuff the finacer will try to sell you, its a waste of money. They will try to tell you that they can only do certain work at the dealer ship, its a lie. -There is no such thing as a certified used car. There is no organization or standards that are set up that used cars suppose to judged by.