I've sold three batches of guns with
https://lsbauctions.com/ over the last couple of years.
They pick up the guns at your house, auction them via gunbroker.com (
https://www.gunbroker.com/all/search?includesellers=6089078), then send you a check for 70% of the total about 30 days later. Auctions run two weeks with no re-listing. You get a paper trail plus you don't have to deal with tire kickers, taking pictures, monitoring ads, haggling, shipping, flaky buyers, etc.
Okie John