Sealed Bid Auctions - Bids are not posted. The requester selects the winning bidder within a few days after the auction has ended.

Absolute & Reserve Price Auctions - An Absolute Auction starting price is $0.00 and has no minimum price. If only a single bidder participates in an absolute auction, the item must be sold to this bidder at the end of this auction for the price of this bidder's bid.  A Reserve Price Auction has an optional starting price and an unknown reserve price that is not posted. The highest bid at the end of this auction must be higher than the seller's reserve price to be a winning bidder.