EBay does not handle complaints, bad users very well as far as I can tell. They have made it almost impossible to leave negative feedback. I was selling some brakes and the winning bidder never paid for them and wouldn't respond to messages. I was unable to leave negative feedback, and his eBay profile rated him 100% and included no bad reviews. I doubt if I was the first person that he scammed but how would other sellers or buyers know if eBay doesn't allow negative feedback?