It really depends on how far it needs to be moved. If it's not that far you could just pull the empty trailer back with a car or mini van. I've seen truck box trailers that were built on light frames, and I've seen them built on the truck frames with the truck rear end. Those types are really heavy.
There's not much to taking them apart. As I recall you'll need a 1/2" and 9/16" ratchet and socket and and bring some extensions. If it's still bolted down to the chassis you might need 5/8" too, but I can't remember the size exactly. Don't forget to bring a swivel. It's safest to just bring full wrench and socket sets - include 1/2" and 9/16 deep well sockets. Vice grips might be helpfull too.
You'll probably need a side cutter to cut free the wiring.
Also, you'll need a 1/2" square socket to remove the bed strips. The nuts on the bottom of the strips are square (at least they are on wide beds). I didn't have one when I needed it at 2AM so I used an oddball 1/2 female to 1/2" female swivel that I've had for years and never found a use for. I just welded it so it could no longer swivel and it worked fine.
