simple answer , they aint ..
this is s stooge suction as we call em here in OZ
you buy your bid, if you bid 1 cent cool , but to buy that 1 cent may cost you $8
from there terms page
Purchasing Bids / Bonus Bids
Rights to bid in an auction ("bids") must be paid for by users prior to online bidding. Bids can be purchased in packages ("Bid Packs") at the prices in force at the time of purchase. Unexpired bids, from a Bid Pack or otherwise are not refundable. No partial refund of gift certificates or Bid Packs.
Payment can be made by credit / debit card, online check or via payment agents. Should a payment not be honored by a user, a returned payment fee of $35.00 will be charged to the user. Certain bids (e.g. some "Bonus Bids") are valid only for a limited time. Upon expiration of the time stated, the bids expire and no refund is available.
How to Place a Bid
Users can bid in two ways online. Bids can be placed by physically clicking on the bid buttons, or can be placed automatically using the Bid Butlers application. Once a bid is placed, it is deducted from the user's bid account.
The Bid Butlers allows bidding on an auction even if they are not online at that time. The Bid Butlers automatically submits bids according to the specifications set in advance by the user. The user is prohibited from using bidding software not authorized by Guns4Pennies. Doing so will constitute a Breach subjecting the user to immediate disqualification.
How An Auction Works
With each bid placed the price of the item on which the user is bidding increases by the amount designated on the Website by Guns4Pennies. A bid submitted by the user conveys the willingness of the user to enter into a binding contract with Guns4Pennies for the item offered at the price of that bid. In the event that bid is the last bid made at the end of an auction, the bid constitutes a binding contract with Guns4Pennies to purchase the item from the seller / FFL dealer of the auction at the bid price and under the conditions set out in the pages which provide the details for each specific auction.
Each new bid placed resets the "countdown timer" which displays the time remaining in the auction. The auction ends when the remaining time reaches zero. The user who was the last to bid then wins the auction. All other bids on the item expire and, as indicated, are non-refundable. The last bidder is determined according to the records in Guns4Pennies database. Guns4Pennies determination of the last bidder shall be final (save in the case of manifest error).
We would like to advise all users to monitor their bidding practices. Placing bids online at www.Guns4Pennies.com frequently or repeatedly can incur high costs. Users should therefore pay attention to their bidding practices and check their charges regularly.
its not just the selling price in the auction but the fee's and levies they charge you , thats is split with the seller and it has the potential to cost way more than other auctions as to calculate a defined total is so hard to do . you spend more thinking you paid X but then there Y and Z and back to A ....