Here's a link to the picture of the hitch dolly I built. Someone mentioned they use a $10 furniture dolly. I have two of these at home but they cost me $20 each but they did not fit my hitch well enough. So for 10 dollars in parts (and my time being worth nothing) I made this one to custom fit my particular Valley 16K hitch.
http://s658.photobucket.com/albums/u...Hitch%20dolly/
I hope the link works.