In the early 80's, the Trapper John character from M*A*S*H had his own spin-off show where he was a doctor who lived out of a Winnebago or something like that, in the hospital carpark. I thought that was pretty cool. Also Billy Batson, who would turn into superhero Captain Marvel (Shazam!), travelled aimlessly through (presumably) Southern California in a Winnebago also.
I'd be happy with a modern-day-but-still-clunky Brazilian built VW Kombi with all the gear (soon to stop production)
Thanks for the input - I googled "Winnebago" and I see some interesting designs. Still, I am adamant about exploring alternatives to the traditional water/sewerage/kitchen school of thought.