I'm in a bit of a peculiar predicament that leads foamies to be quite intriguing for me beyond the having a lightweight vehicle.
You see, I'm a cheap bastard. I constantly research the best price for things and smack myself if I wind up buying something for even a few bucks more than I could have gotten away with.
At the same time, I'm really not hurting for money by any means. Both my wife and I work at well paying jobs and we have no children so our savings accounts are ripe for plundering.
So for this build I'm going to have to balance out lightweight and quality with letting me feel like I'm getting a deal. I already picked up a Harbor Freight trailer on sale and with a 25% discount coupon. It's cheap as hell but it could be lighter. Considering I'm building out of foam that's not as big of a concern for me. I just read one guy in the big thread mentioning that torsion axles could cut a big chunk of weight out.
I am opting for fiberglass because, despite being cheap, it seems like it may be a worthwhile expense for adding some longevity and durability to the build. Paint and canvas seem to be working quite beautifly but fiberglass should trump the strength and durability while only adding maybe a couple hundred bucks more to the build.
It seems like nobody has been looking too deeply at the polyiso foam so far so I may be able to provide the opportunity to add a bit of a new spin and experience to foamies here. I haven't drawn out my plans yet but I think I'm going to go with 1" polyiso foam with fiberglass and polyester resin. The foam will be for a bit of insulation and to give a base structure. The fiberglass will provide the strength. And, as mentioned previously, I'm going to aim to make it a pop-up style to give some head room. My primary decision I need to try to make first is if I'm able to get a bed that runs perpendicular to the trailer in order to get some extra floor space. My wife is 5 feet and I'm 5'6" so it may not be much of a stretch to have a notch for foot room hanging off the side somehow.