Hi and welcome to the forums.
First question is, do you want a trailer to camp in, or a project to work on?
If you decide you want a trailer to camp in, then you could probably park it at a storage lot and do a few little fix-up projects without getting on anyone's nerves. If you want a major project, start out by getting good and educated about the scope of the renovation you are willing to perform. If you need to do a shell-off rebuild, you are going to need a lot more space than just some interior spruce-up work. Try getting your hands on the back episodes of "The Vintage Airstream Podcast" (The VAP), as they go over most aspects of repair/rebuild of vintage trailers.
I guess my recommendation is that while you look for an Airstream, you should also look for a rental house with a backyard or driveway that you can work in. I have a very small yard, but have managed to do a shell off of a 21' trailer. Depending on how involved your renovation project becomes, you are going to need about half of a garage worth of tools, workbenches, etc..
I work on my trailer nearly every day, and most of both days every weekend. I just hit the two year anniversary of its purchase, and it still has no interior, as I have been working the frame, shell, windows, leaky roof, the awning, etc. (and I really didn't want to do a shell-off when I hunted down this trailer). If I had to put all my tools in my vehicle, drive to a storage lot, and then pack it all up again when done, I probably would take 10 years to finish this project.