Yes, the factory in Jackson Center can work on Airstream trailers to some extent, and yes, they are expensive.
If your trailer is relatively new (< 20 years), they can do pretty much anything, including replacing Al panels, however, unless the trailer was involved in an accident, the Al skin is the least likely component to need repair.
If you find a vintage trailer, the folks at JC can do some work, but often will refer you to P&S trailer in Helena, OH, who are experts in referbishing older trailers. They are especially good at polishing the skin.
The more likely things that will need attention in an older trailer are:
- Plywood subfloor: these are infamous for rot, especially around the door, rear bumper, wheel wells, and bathroom, and under the windows.
- Axels: the rubber inside vintage axels can harden over time.
Everything else, from appliances to electrical and plumbing systems are pretty straight forward and you can often DIY, if you're handy and enjoy that sort of work. Any AS you buy, new, used, or vintage will require periodic maintainence and care; it's all part of the fun. This forum is full of informative threads and no matter what issues you'll face, there is probably a number of people here who have an answer, advice or experience in fixing the same problem and are happy to help.