We have a 2002 Safari 25 with the rear queen. We both really love it. It is a good size for a couple. I agree with the previous two replays. I would add that you need to check around the inside perimeter of the floor for signs of damp or rot. A handheld moisture meter would be a very handy tool for inspecting an Airstream for leaks or floor rot. I bought my moisture meter on Amazon for about $25. It will probe through carpet or vinyl.
The windows in our Safari are not fancy as compared to a new Airstream. But, they work very well and I have not had any problems with them leaking. So I am extremely happy with our plain and simple windows.
The original air conditioner on ours was an 11,000 btu unit with built in controls. It was barely marginal in the summer on days that we traveled all day and then tried to cool the trailer at night. Sitting still all day in a camp site with some shade was fine for the air conditioner. We swapped to a 15,000 btu heat pump last summer.
Routine maintenance issues we have had: tires, brakes, bearings, caulking, door adjustment, door gaskets.
We also removed the old carpet and installed a combination of carpet and engineered flooring.
I believe my wife would hire a hit man to eliminate me if I ever spoke of selling or trading our Airstream.