Yeah, I have the hauler with the drop down from the ceiling bed. Sorry to chime in on this so late, but I felt my ears burning through the meds. I hadn't been on in a while but with 7 years building trailers and 20 years repairing, customizing and modifying RV's I figured I might be able to provide some insight. I might have a line on a few options depending on the total of requirements and concessions. For a non-toy hauler that you could setup with a bike rack on the back that is teardrop-esque with a bit of welding or bolting of hardware there are a lot of options. If you're looking at interior storage options there are still numerous options, like finding a model that has a bunkhouse option that you can pull out the bunks and add a door to load and unload through. Most all market options short of toy haulers would require mods of some sort of course and cutting down on what you actually have to build would be beneficial. The door for access is the easy part as there are companies that make custom doors. Walling in and sealing off is easy enough as well. The real question is how much work would you like to do... BTW, DSM8, loved the reading materials, I still have them to return. Perhaps we could go through a little of a brainstorm/planning session for your project, we know I've got time to spare. I'm on the 5 year to a solid femur plan. They finally set some anchors in my shoulder to tie off those rotator cuff tears and they're healing nicely, but this is about trailers, not me thankfully, they're a lot easier to repair. It's all fun to me.