I'm Retiring to a Trailer, and I have a LOT of vintage equipment. What to do?

TMR.  They will. take it all through buying or consignment 

I don’t know if anyone else wrote this, but the collection is certainly worth a reseller sending or coming with a truck. So your scope is pretty good on this in terms of finding neighboring state dealers. The hard part is finding that dealer, but that really is just a little internet searching starting in your state, then Branch out to the big names in vintage audio two states away...and so on. I think it's completely possible that you could solve this problem in a couple of days with a few well placed phone calls.

Somebody will bring that truck. Christ, if I were anywhere near you I’d love to cherry pick a few things.

Like my wife would want me to walk through the door with one more thing..

Resist idiots like me taking all the good stuff and find that dealer. Two days on the phone will get you that. It’s worth it.

Congratulations on selling your gear.  I’m 73 and have been selling off my collection in pieces where I’m down to 2 systems.  What I found interesting was your love of things JBL.  In 1990’s and first decade of 2000, I had a side hustle with a friend going to garage sales in Sarasota, FL area and then reselling on EBay.  If I found something I loved, I kept and enjoyed until something else caught my fancy.  Since Sarasota is fairly affluent and everyone and their brother was moving there during that time period I went through about 35 pairs of speakers, the bulk being vintage JBLs.  One pair I owned that I did not notice in your list and really wish I had kept, were a pair of JBL Aquarius IV S109s.  One upward firing woofer and a tweeter that fired into a diffraction plate in the rear.  I called them my "Bose Killers".  I spent 3 weeks refinishing with the help of a custom furniture building friend and a fellow who did my refoaming.  They were amazing.

Well I'm sure your ad here worked wonders for you. 

Where I live, we had some really good technicians that bought up vintage equipment and did restorations. Even things like Edison cylinder machines, art deco radio consoles, early idler drive turntables, essentially anything that presented itself as a good project. If equipment wasn’t working, they also purchased that so they could salvage the parts. I’m just mentioning this in case you have some things that didn’t sell as easily as the prime stuff.