I looked at those tow dollies for a utility trailer but never bought one. I have used an old John Deere 112 lawn tractor to move a medium sized boat around on my property. It has an old school cast iron kohler engine, rear wheel weights, tire chains and a large stack of plastic covered weights from a home gym system fastened to a rear frame which also holds the ball. It could use front end weights and it would be easy to weld up a frame work and add just about anything as weight. Front weight would be needed as I could see the front end coming up when you put that much tongue weight on it.
It depends on your mechanic and welding abilities and availability of cheap used equipment in your area.
If you are using one of those dollies on dirt and grass it may do better with tire chains.
