[VAC] Looking at an Airstream

[WPrice5496@xxxxxxx]

        Aside from checking out mechanical systems and general soundness, 
what points should be checked in determining the general condition of a 
vintage Airstream.  
    I will be going to look at, as the add states, "70 Airstream 
International, 30 foot long, ac, $4000."
    In speaking to the owner on the phone, I am told all systems are go, but 
there is an inside leak of water from the AC unit, is this a big deal?
    Any advice would be greatly appreciated, love the group, I'm learning a 
lot.  I will take my digital and take PICS when I see the unit, and will post 
them in the hope of further guidance.
                                                                Walt in WV