I really want to thank this group for giving the information over three years ago to start building with foam. I was a member then but never posted anything on the build except maybe a couple comments. I started with a teardrop type that could also be loaded on the truck as a camper. I used it both ways to travel thousands of miles. The following year I built a 7x11x7 tiny house trailer with EXP panels with FRP glued to the inside and thin wood glued to the outside and exterior cedar trim for structure; with french doors on the back and a folding deck and roof. Last year I found a 1976 Dodge RV and was able to mount the trailer on that platform and construct a front section to tie them together. I will try to insert pictures and construction details if anyone is interested but for now pictures are on my facebook page "Kenny Foust" and a guy made a live video at an event in January where I did describe briefly the general construction at:
https://www.youtube.com/watch?v=rmAAeWafz0g&t=4s
Excuse the rough video and I am waiting for an edited one that was made. The facebook page has a the updates since then with 600 watts of solar.