Hey Moof, check razortrailer.com , I bought one of these last year to haul my bike to AZ where I live for 7 months out of the year. It is a simple design, a main frame and a deck is attached by a full width hinge at the very rear, it uses a boat trailer hand crank winch to lower and raise the center deck to ground. It uses torsion axles allowing the deck to lower to ground.
I made 1.5 round trips so far, the cheap Walmart trailer tires he used wore bald by the time I got to AZ last year from NC. I replaced with a decent set from discount tire and they made a complete round trip with little wear. I don't like his welds but none have failed, the paint job is cheezy, I had to redo some aluminum diamond plate trim on the deck, 1/2 the pop rivets failed 1st trip, replaced with tech screws. I could have easily fabricated this trailer myself had I known the design is not complicated. I paid 3k for it with a few options. Prolly can build it for under 1k, Check it out.
I'm up to $450 on a modified boat trailer. Steel beams, a steel floor screen, and stronger leaf springs have been added to the trailer. Add in the 6 ft 1500 lb ramp I just purchased and I'm up to about $700 on a dual motorcycle trailer that can easily be used for any utility vehicle and/or general use.
My buddy and I are going to be testing out the chock placements next weekend so we can figure out the best center of gravity needed to haul. I don't want to put too much weight on the truck tongue and everything is coming together pretty well, so far.