Colliehauler is dead on. In the early 2000s we bought a Trail-lite hybrid, and camped extensively with a couple who bought the exact same unit. These were built with laminated structure on all six sides. It has aluminum tubing spaced at remarkable distances, IIRC 30" on center in some areas, expanded styrene blocks to fill in the space,and layers of THIN Luan plywood glued to each side. The floor was slightly stiffer, since the thin Luan was doubled there. I'm a big guy, and noted that within a few months of regular use, I could feel the floor deflecting between supports. By the second season, it was apparent that the floor was starting to sag, and felt soft in traffic areas.
In 2002 we did an extended family vacation from the east coast, to San Diego to Alaska and back. By the time we returned it was apparent to me that the unit was simply too lightly built for the kind of camping we enjoyed. The frame had sagged on both ends to the point that the lower kitchen cabinets had torn off the wall and there were other signs that it wasn't going to be a "keeper".
By comparison, the other family with the same model, still has theirs today. The only reason it still rolls is that the hubby is a true farmer. As in, nothing ever gets tossed out, you use everything until it's scrap, and if you can't fix it yourself, learn how. This guy took a week vacation to rebuild the floor, including adding a considerable amount of structural steel work to the underside to keep the floor from totally failing, and replacing a lot of luan underneath, as it had significant rot. He also bought a carport to protect it from the rain and snow it gets hammered with, since the roof has developed a significant sag. Unless it is parked with the front or back tilted way up, it pools a lot of water on the roof. At this stage the trailer is significantly heavier than new, and it has no real value, since even a quick glance underneath would make it clear that it is really a patched up mess.
