Sorry. I should have talked about the inspection of the trailer. Okay here we go.
Do the bumper bounce test over both frame rails. Stand on the bumper and bounce like getting ready to dive off the diving board. Look for any separation between frame rail and body. Any movement means the rear frame rail bolts have rusted away.
Bring an ice pick. Poke around the subfloor especially in the rear compartment. Many of these trailers have floor rot in the rear. Also check under windows and just inside the entry door for floor rot.
If the axles haven't been replaced, they will need to be replaced. Figure $2600 for two axle assemblies delivered.
Examine the body for dents and scratches. Body damages are the most expensive repairs. Peeling clear coat is common, maybe 100% on these old Airstreams. It can be stripped off. Check the belly pan. Many times the rivets corrode loose.
Check all appliances for good working order. Fridge, AC, furnace, water heater, water pump, stove, etc.
Pressurized the plumbing with a hose and check the faucets and toilet operation. Squirt a little water in the fresh water tank and test the pump at all the faucets.
Check all the electrical items including lights,
12v converter, outlets and the like. Tongue jack should work. 2 5/16 ball should fit and stay in the coupler with the lock down.
Tambour doors on cabinets are problematic. Horizontal ones are worse. See how many sticky ones there are.
Expect to find mold, mildew and the like. It can be cleaned up.
And anything else you can think of...
David