In my neck of the woods there are gun dealers that only travel the shows and buy firearms from those of us no longer able to use for whatever reason and because they are using as an excuse to do something in retirement they will generally offer decent prices.
I had a buddy who did this for years, actually how we met, till he passed a few years back and he would always offered fair prices to widows cause he was in it to support his addiction not to make a ton. Not saying he didn’t turn a profit but he wasn’t growing rich on the deal either once you factored his costs of travel and what not.
If you have someone in your life who can assist, maybe send them to local gun show and scope out the booths. Look for the retired looking gentleman (or gentlewoman) with the classic firearms on the table and little to no “plastic plastic guns” and see if they’ll work with you.
Still do your research on a couple of key firearms on the collection and have him come out and see what he offers. If he offers a reasonable price (you determine what the convenience discount is worth) than you can do business with them.
Also agree on partnering with a friend if possible to help in case of unforeseen circumstances. I have a couple of friends who have agreed to assist my wife with breaking down and safely storing my collection for my heirs for when they come of age (oldest is 3 currently).