My first was Eggbert a cargo tear for my motorcycle it has 7/16 OSB sides. It was a real quick build and at 3x5 the body with floor was light enough to toss easily into a pickup.
My 2nd was 5/8 OSB with 1/4 " luan veneer outside and 3/4" foam board with 1x4 spacers to reinforce at the panel splices them 1/4 luan panels inside. The 3/4 void gave enough room for the electrics all mounted in 1/2 depth carlon boxes just like your house only shallower.
My 3rd is a work in progress and I intend to use 3/8 ply bead on the outside and 1/4 paneling on the inside with 3/4 foam and 1x4 reinforcements.
So I guess I don't have a clue !
Anyone up for paper mache ?
All of my trailers do what they were designed to do and function well there all just different

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