GunBroker, and Auction Arms, are auction sites, wher you must register with a credit card to bid/buy (or sell) - and where items are auctioned off to the highest bidder after the particular auction has run the course-of-time (length) chosen by the seller.
Some sellers choose to set a hidden "reserve" selling point, below which, any bid will not take their item.
Some sellers also choose to include a BIN (buy it now) price, which allows any buyer to bypass the bidding process, and immediately purchase the item for the BIN price at the specified terms.
IMO, an internet gun auction site is pretty much like any other - they are simply conveyences where other parties may buy & sell firearms & related gear.
EVERY buyer & seller - whether an FFL with an inventory listed, or Joe Blow with one gun to buy/sell - needs to do their homework, so that:
Their item(s) will sell.
or
They are successful bidders (buyers).
To achieve the above goals, one must "know" what they have to sell (or bid on, buy) is worth - keeping in mind that while a picture's worth a thousand words, a complete description (1,000 words) is also desireable for presesnation,
AND
"presentation" is EVERYTHING" - since it's how an evaluation is made.
As a seller, your item will have a better chance, if a better presentation is made.
As a buyer, think how hard it is to assess a poorly-presented item.
FWIW, I have successfull sold firearms on GB & AA, starting ALL my auctions at $0.01, with a reserve set somewhere between the real world wholesale/retail/street $$$.
OTOH, I have also successfully made purchases by knowing in advance the true market value of whatever I was seeking, and then limiting my top bid to my assessment.
ALL auction sites must be somewhat biased towards sellers - after all, the sellers are the ones posting the ads that generate the auction owner's commissions/income.
To believe an outcome of a dispute would be otherwise would be an unreasonable expectation IMHO.
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