I built my own trailer. Its made of 2x4's and wheels. theyre just small wheels (stolen off a grocery cart) but they work. I basically made the dimensions 4 inches bigger than my box so essentially it is 10'4" long and 1'4" wide. And than there is 2x4's on all the ends sticking up vertically so it doesnt fall off. worked for me and really easy and cheap to make.
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