I am not extremely familiar with the stamp market, but I am pretty familiar with selling antiques and coins through
ebay. From time to time I get a listing that goes crazy with international bidding only to sell and the buyer to have 'questions' about the item, problems with their paypal, or asking to work out a payment plan. One story from last month I had an item go up to $2875 in bids and when it was checkout time they claimed the item was too expensive. Relisted the item after a week of unsuccessfully offering it to the next highest bidder. The item sold again for $2600 and the buyer once again was complaining but this time about the shipping tax his country would place on the item. Decided to just list it again for a Buy it now for $2500 and ended up selling it for $2300 to a completely different buyer. To anyone viewing it from the completed item perspective this may have looked like shill bidding, but it was actually the buyers fault. At any point after the auction ends you can just cancel the auction and they refund the final value fee. Another thing to add is that when I get an item I sometimes look for the highest selling example of that item and highjack the title. In the stamp world it can look a lot more exact as they tend to only offer one or two pictures. Now, I do agree that there are deceptive sellers on
ebay but I am just implying that not every one that fits this criteria is doing that.