Charlie, if you are going to pull the body off, don't overlook an older motorhome.
I bought this old Champion a while back, good running 440/727 on Dodge truck chassis. Interior was shot and I ripped it out to use as a storage shed.
It was $200.
There are lots of them out there. Might work for you.
Or how about a newer school bus chassis. Pull the body, add your oldtimer body, and it's nice and long to build your home away from home on.
Older and non running school buses go for under $1000 around here.