Got bit by the bug almost a year and half ago and recently took my first big steps. After much research and planning I bought a small sheet of 1/2 inch foam and built a mock up of the shell in 1/4 to test how rudgid it would be. I wasn't sold on foamies (still not, can't figure out that PMF, it doesn't look that hard but I'm missing something) but weight is a huge concern because the tow vehicle will be a 4cyl nissan rogue rated at 1000 lbs. I've decided on a hybrid, mostly 1 1/2 foam with studs here and there for structural support (likely around doors and hatch).
I also picked up the HF (4x8) 1200lbs trailer, put it together over memorial weekend, been making small material and dump runs with it and checking the bolts to see how I feel about a bolt together trailer. I think next week I'm going to take it up to a local shop and have them weld it together, add an extra bar to help with tongue weight if the cost can stay under budget.
My design right now will be a 5x8 Rimple. Doors on both sides, while I'm not looking forward to it I hate spending money (ironic) and will be building the doors on my own. No side windows but a sky view window in the top out of plexiglass (maybe?). I've already built the sub floor but I'm really sure I'm going to take it apart and build it differently since I slapped it together just to do it and didn't check for square. I'm also going to bolt the sub floor directly to the frame instead of making it a removable unit that I could bolt together down the road. I have some photos of construction so far and I'll upload once I get them off my phone.
Howdy!