Just built a trailer a few months ago but still keeping an eye on what's being talked about. Check out this post here:
Snow Bear Trailer
I ended up going with a Harbor Freight and building a box, then putting a deck on top of that. Mines the one with the grass
I've already pulled it from Denver to Taos, BV several times, upper C without incident. Brendodendo's reco's are good too. I plan on adding Buddy Bearing at the end of this season. Whole thing, including lumber was under $500.
On thing worth point out about Harbor Freight trailers is that you have to assemble them yourself. Not a big deal, but the DMV make you have a VIN certification done by the State Sheriff. Not a big deal either. It did suck that I had to stand in line at the DMV to find this out though.
I'd be happy to share specs if you want.