I think we could build our own fiberglass boxes, once we get out of the campgrounds. I have an old Gougeon Brothers on Boat Construction
book that I picked up at a library used book sale. It has a lot of info on how to fiberglass using the West System
Epoxy ("a versatile, 2-part, marine-grade epoxy that bonds and coats fiberglass, wood, metal, fabrics and other composite materials to provide superior strength and moisture resistance"). I found this system back when we had the Eagle 05. After much research, I decided the West System would be what I used when we built the "Fiberglass on Plywood Tanks
" holding tanks for the Eagle. But we dumped the Eagle and ended up with the Blue Bird. We already had a couple of ABS Rocket tanks and then we got the bargain RV waste tanks so the Fiberglass on Plywood idea got shelved. And then I ran across the book. So I just picked it up as a "just in case future reference" book For like $1 or $2 dollars (hard to remember since I bought about $25 worth of books - and I bought a LOT of books that day). Great reading. But after doing much research on buying ready built underbelly storage boxe$$, I'm back to thinking West System on a substrate again. The Gougeon Brothers book is all about building a boat but the techniques would be similar. They are the ones who developed the West System. Once we get our own place, we can build a couple of forms and fiberglass our little hearts out.