Ken, I do not have any software but I'm one who will stare at a piece of paper until I realize what it is I want to do. As soon as I completely decide (think I might have it) then comes the fun part. I have always wanted to have a reason to make a blue print... And now I do.
Half, I have already been to 2 RV dealerships and have a good idea for what I would like to do. Also, going back to the "blue print" I will keep in order to know what is put where incase I need an "eagle eye" placement of a screw or if I do any sort of plumbing, I will have trap doors for the joints etc... I don't think I will be going too large the first go around, but you never know... I might just decide to all out, but prob. not.
I believe I will be using 3x3 angle for the frame with a bunch of bracing, then ill switch to either thin tubing for the frame under the bed and maybe the rest also, or look into... I don't know exactly, tin studs you find in office buildings.
Right now my trailer has the plywood decking I got from work... It's the best type of plywood you can buy, and I'll just use newer next time. My plan for the outside is 1x4 or 1x6 pine or cedar or something, but that's where I'm not 100% on how it will be done and still look Perty.
Again, thanks... and camp on!