I put together this rig for advanced riding school and track days. My wife and I do one a month from May-Sept and got tired of renting or borrowing trailers.
The trailer is a 5x8 mesh floor with ramp from Tractor Supply. I got a 5x8 sheet of 5/8 sheathing plywood and sealed all sides of it with paint. The top is coated in textured outdoor porch/floor paint to keep the bikes from sliding while loading or unloading. Our driveway is pretty steep, so this had been a great feature. Wheel chocks are from Harbor Freight, and are sturdy and safe. Not the greatest chocks, but for $30 a piece they'll work until we drop the big bucks on a pair of Pit Bull Trailer Restraints. The chocks are bolted to the frame members of the trailer at the rear, and through the plywood and mesh at the front with 3" diameter fender washers. I drilled the top rails and installed u-bolts for tie down anchors. All hardware is stainless steel, with nylock nuts everywhere. The trailer is just big enough for two bikes, still small enough to fit underneath our deck for storage, and light enough to easily walk it up a steep hill in the yard.
All of that cost us $650, and a couple days of work on the weekends. Oh, and we tow it with my wife's Durango R/T (seen here in pony-hauling guise). When kept under 70mph, the bike trailer costs about 1 mpg with two bikes and all of our track gear (EZ-up, chairs, cooler, tool bag, riding gear, my fat ass) loaded up.
