Well, I abandoned my idea of turning my little cargo trailer into a mini-camper, and bought, instead, a former Coleman pop-up that had been converted into a 7x10 full-height box. Since it lost its identity two owners ago, I had to get it weighed as part of the process of getting a new VIN assigned, so I took it over to the local waste transfer station. I could not believe it still weighs almost 1800 pounds, when it was rated at 1875 when it was a fully equipped pop-up! I mean, it no longer has the bedroom ends, the table and long couch have been removed, as has the little box right inside the door. So there's almost nothing still there and it still is almost too heavy, given that I have to add insulation, some sort of wall covering, and also a thin waterproof shell for the outside. The framing for the box is 2x2s (actually 1 1/2 x 1 1/2) and 1/4" OSB, which I wouldn't think would weigh that much. What gives, I wonder?