John J Hallinan III uses multiple accounts to make shill bids on auctions he lists as BIGJJSTUDD on EBAY. He has been performing this scam for at least 2 years now. Recently he made his feedback list private so that buyers/bidders have no idea whatsoever that these accounts have close to 100% bidding history with this account.
He will also use this accounts to bid and purchase auctions from his competitors. He does this to research their business practices and sometimes to leave negative feedback.
He also employs this tactic to make his similar auctions appear to be lower in price, he does this in order to drive the price up so that the bidders will purchase from him instead. The account he uses
to do this will then not pay for the auction.