When liquidating an estate with a significant number of guns, I have had very good luck contacting and using an auction house that focuses on guns.
Often for collections they will come to you, give you a receipt and take care of everything.
One of my local auction houses I have used frequently has always done good by me.
You give them the items ( mine will take pretty much everything -guns ammo reloading supplies and equipment etc
It saves a grieving family a ton of hassle.
They take pictures, post the gun on line usually on big sites that attract a nationwide audience ( people that wouldn’t be reached any other way) like proxibid or hibid.
Once sold, they handle the shipping ffl etc
Then a check appears in the mail.
Yes they take about 20% or so in most cases for a sellers premium but even with that they usually get top dollar for hammer price, often a lot more than you would expect.
Over the years I have used a couple auction houses in this manner for roughly 100 guns. Only one time did I not end up getting more for a gun than I had into it.
In a couple cases I literally got thousands for a gun I bought years earlier for a few hundred bucks.
Instead of having to meet and coordinate with potential buyers, deal with transfers etc by yourself, it makes things so much easier, and really does get you top dollar