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Over the years, I've sold a lot of firearms on GB, and have bought a few - during which I learned a few things.
To register on GB, you must submit a credit card number, so you can be charged for the ad costs and the commission (if it sells).
Then
Clean & polish whatever, so it will look it's best - there's only one chance to make a first impression.
Take & post a LOT of clear/close pics, plus a full-length shot (because a picture can be worth a thousand words).
Read as many other seller's various descriptions as you can to edumacate yerself about how to compose a description that will help the gun sell.
Write out a lucid description statement, including your special input(s).
That said, there's a few things you should always include:
A) the condition as compared to new (NIB, 98%, 70%, etc) of both stock & metal.
B) the chambering
C) the barrel length & the condition of the bore (pristine, worn, pitted, etc)
D) the overall operating condition and any known malfunctions.
E) the disclosure or disavowal (say it has no etc/etc) of any of the known usual suspects that affect condition/value (rust, cracks, scratches, alterations, etc).
F) include this statement: sold in "as-is" condition, your FFL should agree to accept shipment from a non-FFL (me).
I sometimes include the statement : no trades at this time - Thanks
It's up to the seller to set a starting bid point, and a reserve (if desired) and the length of the auction.
I usually do a 7 or 14 day auction, depending on the item and the season (demand varies from time to time).
You can (roughly) figure the cost of shipping, and either add it into your selling point, or list it in the ad's shipping costs.
I usually set a starting bid that's about $100 under average selling prices, unless it's a real hard-to-find rare gun that's in demand right now (do your homework)
Any citizen can, of course, ship directly to any FFL holder, anywhere - except where the FFL won't accept shipment from a on-FFL holder, or a (buyer/seller) state law says otherwise.
Long guns and handguns can be shipped (UPS/FEDEX/etc) interstate; long guns can alternately be mailed (USPS) - but handguns can only be mailed by an FFL holder.
If the buyer's FFL will accept shipment of a long gun, I usually mail it (USPS).
If a handgun is involved, while it can be shipped (UPS/FEDEX) to an FFL, I usually obtain a USPS Flat Rate Box (set fee, for up to 70lbs) and have a friendly FFL mail it.
If I want to sell a firearm that I want to receive a set dollar amount for, I usually list it in one or another classified section of the several forum's I am registered at.
Good Luck Doc ! .
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