People jump into a restoration project for two reasons.....to keep it themselves and use it, or to resell the vehicle.
Here is a link to a really nice Airstream that has not sold.
AirstreamThe coach has some age, and it will get some bidders for resale, but not enough to off set the cost of the restoration.
Now, if you want to buy it for your own use, and you can handle ALL of the restoration, than it MAY NOT be a bad deal. Then again it may be a money pit that you will never get to enjoy. If what you see scares you, then the hidden problems will terrify you. It sounds like this is one to pass on.