I've been looking for a bed cover that would be practical for a fiver tow vehicle. I needed one that could be stowed easily while towing. I finally found the Advance fold-a-cover.
http://www.advancecover.com/
This one has four panels and stows in the front 25% of the bed so it stows ahead of the hitch (at least it is on the long bed).
When we are on the road we use one of those louvered, notched tailgate to avoid accidentally hitting the tailgate with the hitch pin. Now we can put the cover out when not towing and get maximum efficiency even with out a solid tailgate.
The thing cost about 750 bucks including shipping and I installed it in about two easy hours.