I got this beauty at Harbor Freight for $250. It's exactly 4'x8'. It won't be carrying much like this as I need to get a sheet of treated plywood for the bed. There are rail holders on the side so it will be easy to make side rails too.
The hitch and wiring kit for the car was only $150. Installing the hitch on the car was by far the hardest part. The nice thing was that the manufacturer has threaded holes already in the frame so it bolted right up. The hardest part was the threaded holes were full of rust and the hitch place sent me the wrong bolts. After 1/2 a can of WD-40 and 2 trips to Lowes I finally got it installed. No need to do my P90X workout after that mess.
The best part is that this thing folds right up and doesn't take up much garage space.