Other club members and myself have gone together on auctions to make a bid neither one of us would/could have made alone. Of course, we don't do it unless there are multiples of a chip we both want. And even then we often get out bid. Been there and done that for each scenario you mentioned. For now, as a collector only, it's us against them (buyers vs sellers). However, if I wanted to sell something I would change hats and it would be me against all y'all. I have never sold anything on Ebay and probably never will. I can understand things from both sides.