From antique and vintage firearms to the latest and greatest guns and sporting rifle models, firearms auctions are a big business in the United States. Purchasing firearms at auctions requires a little education as to the regulations and laws involved in the purchase and transfer of firearms. An FFL (Federal Firearms License) holder is needed in the transfer of ownership of many types of firearms across state lines, and within most states as well. If a Seller says that an "FLL is required", that means the Seller won't transfer the ownership of that firearm to the Buyer without a valid FFL holder on the Buyer's side to transfer the weapon to. Most gun stores (of which all have an FFL) will manage the transfer of the firearm for a small fee. Be sure when bidding on firearms at auction to read the terms involved.
If you are considering buying or selling firearms at auction, a professional auctioneer can offer valuable advice. Auctionservices.com has created an Auction Community that is free and open to the public. Members include professional auctioneers who can answer your questions.