Checked into polishing before I bought my motor home, did a lot of looking and reading what others had tried. From stripping the clear coat, to working thru the different grades of polish (from course to fine) I decided I was not up to it. There was a guy or company that was advertising they were polishing airstreams. They had some examples of work they had done and it looked pretty good. And now for the other shoe... It must be quite a chore because they charged $125.00 a liner foot!!! That would mean it would cost about $3875.00 to get my 31' polished
. I decided that the small imperfections in the finish are "beauty marks" and the add character to the airstream.
I've had some luck with these folks as far as parts, I know they are not independent but they treat you that way. they are in Huston
http://www.pplmotorhomes.com
Good luck