We had a dolly like that at this ghetto u-haul i used to work at.. they rented the big ass covered trailers too.. they had a proper dolly with a brake on it but was broken for the year i worked there.. had a new kid try and move one of the big ones with the dolly, we used to move them with another uhaul truck but this kid friggn lifted it up and thing whipped up and rolled half a damn mile down the road.. ran into like 4 cars and crap.. lol.. kids 3rd day on the job and he just leaves right after..
If you want to increase the weight handling capacity you can add 1/8 inch plate to the dolly base platform... while your at it extend the base by a few inches if you need more height
