I am very new to wood working; I have read many threads in this fantastic forum and have studied the generic plans and some other plans posted by different builders. However, there are a lot of things that I do not know hpw to do; the most important one is to fit a design on my trailer bed!
Here is the trailer:

It's a square frame (no metal can be stripped of it to achieve an 8x4) and the dims are 112"x76".
Got the inspiration from WEEKENDER and ended up with this:
(note that for now, my wife and I will only need a rom to sleep in, no cabinets and gallery for the moment; but next year, yes! we should think of building a real teardrop trailer!)(This one can also teach us how to do stuff!)


The spars and supports are 2x3 and the plywood is 1/2".
Do you think this is feasible?
If I had an 8x4 frame, I would have loved to build the weekender......
Your help is highly appreciated!
Please note, I live in an apartment and should do the stuff with minimal tools and freedom!
THANKS IN ADVANCE!