Dave , bowyers have been using boxes like this for years to dry/cure their laminated bows ... I made one 20 years ago for bow-making , and it worked well

... mine even had a little thermostat that kept it at a pre-set constant temperature... (note: Not as high a temp as Nick’s ) I’m sure we could put something together that would work on Foam sheets the same way ... but making a device like that would be impractical for making just one camper... Overcoming the "bending hurdle" would allow you to go into production , easily making many nice curvy foamie’ trailers ...

Just for one build, a 1500watt heat gun should work.
We have put a lot of thought into bending foam, and have easily bent/formed much thinner foam (1/4"-1/2”) in the past (heat formed) .. and the best results always involved a bending jig or form to shape the foam to ... The foam when heated is quite soft and only permanently assumes the new shape once fully cooled ...and on a “form” shaped to the bend/shape you want, is the best way to let it cool to THAT shape ... That’s another large fixture to build ...

Starting to look like a Factory ...
