bed size? hauling abilities w/ double cab?

I'm tossing around the idea of selling the F150 (miles are getting pretty high and terrible MPG) and getting a tacoma. I'll probably get a used one and I really like the idea of the double cabs, probably an 02-04 model. I was wondering what the hauling capabilities are with this small bed. Can I still haul a 4 wheeler or riding mower? I know that I can't w/ the tailgate up, but what about if it's down? Would I need to get some type of tube gate to use when the tailgate is down? Anyone with any pics of their double cab with a 4 wheeler on the back I'd like to see it. Thanks.

McBride