I had to move 3 cupboards (2 large wooden ones and 1 steel one) from room to room. I had only myself and my 78 year old mother to help me. Those large cupboards are heavy, need at least 4 people to move one. I made these dollies, so I could do the job easily. In 15 minutes, moved all 3 cupboards without much effort.
Two dollies, each with two wheels.
Another test video
Just to answer the comment from Rajith
According to the above maths, if the total width is > 2 x height, then this has to be super stable.