I used a Rotozip to cut the profile, doors (at the same time), circular vent openings (4 + 1 times), the opening for my interior-mounted A/C, and both windows. I cut the profile and the doors out at the same time...laying one 3/4" sheet of plywood on top of the other (1.5" thick), clamping guides to maintain a line, and proceeding. My advice...don't try this at home! The tool was a bear to control, and the results had to be heavily sanded for a crisp line. My idea to use the Rotozip, not recommended. On the other hand, cutting the single thickness of 3/4" ply for the circular vent openings was much better. I had no trouble, though the bit jumps around (it's not made for that thick of material), but was controllable, thanks to the anchored circular swing-arm. I also tried to free-hand the opening for my park power cord entry. Not good, but hidden! As to the A/C opening, it was perfect to reach it and cut very close to the adjacent interior wall, whereas there was no room for a jigsaw. On to the windows. The cuts were made in the walls using screwed on guide rails; still hard to control, but not too bad. I measured wrong, and had to enlarge the openings freehand (very hard to control). I had two jigsaws fail me on this build, and one circular saw, and a router tried to impale me...the Rotozip, my angle grinder, and my friend's Snap-on impact and drill did most of the work. If I was to build another trailer, I would use the Rotozip again, but on 1/2" plywood this time. Sample cuts:
- circular vent

- ragged window opening (freehanded)
