Truckcampermagazine - that is literally the one I bought.
It aired out and now no musty smell, it was faint anyway, and fiberglass being not porous…
The floor is two layers of fiberglass, inside floor - hollow space -outside floor, no wood, and does not seem to be foam core, nor foam core on the rear wall where I can peak through. The roof I think is foam core, maybe parts of the walls, but parts sound hollow.
I think maybe there was wood sitting on top of the floor originally. This one had a leak so they took out carpet, and wood, as the truckcampermagazine suggest there was wood.
I will get more lexan or plexiglass as this one is opaque.
I was thinking of visiting a junkyard and finding a sunroof glass to retro fit it, but if it was plastic from factory then I dont mind changing every 5-10 yrs. I dont think auto glass can be cut.
I have to get old trailer ready to sell, so work will come later. Trailers are way easier to hook up. I probably get electric motors for the jacks. Lots of creaking when I do one at a time, even just an inch at a time, its way stiff compared to wood frames.
As for leaks, I dont think the dealer knew about Eternabond tape, they put silicone on everything on the roof seam. I think they did it that day. The tape will make it waterproof for a thousand years.