The active collector community nearby will gobble them up quick if you list them on Facebook marketplace, craigslist, or the marketplace here.
We all have our ideas of what fair prices are. All I can say is if they are cosmetically nice, complete, mold and rodent free, they’re worth some cash and will be brought back to life, after some amount of labor and normal maintenance parts. If they’ve got other issues, they fall into the project category and you won’t get the big bucks. I guess what I’m saying is there’s a fair number between the “Ill take it off your hands” and the ads you see for working machines.
Good luck. If I didn’t have a king pin, I’d be bugging you about that one, it’s a good game. I’m not really familiar with airport.
Dave