Thank you for all of the replies. I may just try my kayak dolly first, but I do not think that it is going to be wide enough. Those wheel on amazon look like a pretty good option, just buy two and bolt them to a board that would slide underneath. I may try making an axle with two wheel and a ratchet strap, but what would I make the axle out of, maybe a 3 ft threaded bolt? The easiest/cheapest might be the $40 boat dolly, although I would prefer not to have to turn the boat upside down, so that I could put my fishing tackle, battery and trolling motor in. Great options, guys! If anyone has any ideas on how to make that axle, please let me know. It would be even better if I could make a long enough axle that I could just take the wheels off of the trailer dolly (which I have no use for), and put them on that.