Well, I think I am witnessing a scam right now. About a month ago I had a bid on a gun with an auction house through icollector. The bids started about 21 days before the actual auction. I was high bidder until about the last 4 days when my maximum was surpassed by another bidder. I wasn't going any higher. 2 days before the auction expiry date I was suddenly high bidder again. Someone else did outbid me in the end.
I had the exact same thing happen today regarding another gun. I was high bidder until yesterday when I was outbid. The auction is over tomorrow and I'm suddenly high bidder again this afternoon. Both times were with the same auction house. Per icollector terms of agreement, a bid once place cannot be retracted. I sent them an email asking what is going on but haven't heard back yet.