Yep foam panel would be ideal. The trailer I hire is roughly 40?mm foam panel and pretty good and ticks most of the boxes. Its about the right size; goldilocks you might say, has a ramp door and you can stand up inside.
If it had a side door and a tapered nose section it would be perfect.
I spoke to ol mate at the hire joint about where they got theirs and lo and behold it actually came from the crowd I initially went to and rejected lol.
He said he had to do a lot of rewelding and strengthing improvements when they first got it and agreed it was pretty ordinary if you know what I mean.
If I'm going to shell out this sort of bucks I don't want the first thing I have to do is get underneath with the grinder and welder!.
The interior fixtures, fittings and indulgences will evolve over time I'm sure
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