and unless OP stated he would not use an alt account to bid up the auction than he is free to do so
Just because 99% of you all here follow "respectable" auction rules doesn't mean that anyone HAS too.
Oh my.
Shill bidding in auctions is a major no no. He may be "free to do so", but people who do such things should be negged to hell. I am NOT saying that the seller has done this, so lets make that clear - I am simply stating that bidding in your own auction is essentially fraud - and if you do it and get caught, don't expect any respectable user to ever deal with you again.