Over many years I have bought cars privately,from a dealer, from a friend, from a relative,from news ads and from notices in the street. I have also bought and sold cars on EBay. My experience has been that you can get a dog from anyone and they may in turn know it barked or sold it in good faith. What does matter is that should it be a pup you have got legal comeback. There is no problem buying off EBay as long as you appreciate that if the cam belt goes within 300 miles, tough. Just be sure you know what you are looking at, don't pay too much and walk away at the first hint of grief.