He will bid on multiple items and then after winning them ask to have all but one cancelled without starting a non payment case or he won't buy the one that he does want. The seller then has to resell the others from the start. He will also search for an item with a small error in the listing that he can use to leverage a refund while getting to keep the item. He will refuse an offer to pay for the return shipping and give a full refund but will insist that he get to keep it and get a refund also (in my case he got over half the price of the item. He is aware that he can hurt a seller with impunity and threatens to do that right away. Don't go near him!