You have good wife Beagle. Mine keeps yelling at me for too many projects I am taking and even I come to the same conclusion that the only way to get what I really like is to build it myself- I know the scope of such project is monumental, so I am closer to Avon full remodeling idea. But they are too small for what I want darn it.
Than even aluminium siding is good, stainless steel is better.
I guess you know already that World is full of similar projects - started, never finish and available for 2 cents on invested dollar.
I've seen pictures of Airstream trailer converted to Sprinter-based expedition camper and that was exiting.
So how about a sketch?