Bottom Up Examination
I would go from the bottom up.
Check the NADA for approximate value or use the search option above.
On the Airstream:
Start at the wheels to see if the axles (top of tires showing) and frame are sound. Then with a ice pick check (careful some owners can get ugly with this one) for floor soundness in bath and below windows or discolored seams. Check out appliances to see if they all work. Windows, dents and awnings are expensive too.
Is it the configuration you want? Twins or Double could mean trouble with loved ones.
Too big to haul or too small for you all?
Any place to store it? Can you afford it?
"Talk is cheap, Airstreams are expensive," Wally Byam.