Hi,
I wonder if you could put lockable wheels on it so It could be used to load a mower into a vehicle. Thats about the only time I ever notice the weight of a mower. With something like a Victa 24, its a bit of a struggle to get it up into a 4WD ute alone. Here I back the ute into the kerb then load it front wheels up first followed by the rear with a bit of a grunt. Local traffic must wait for me but they do not seem to mind if its not very long.
Seems to me you need a rotisserie style stand in there as well so can easily rotate a mower. Handle would be a problem I suppose but I do most underdeck work with the mower on its side (on the ground of course). Always turn them spark plug up unless there is a sticker which says otherwise.
All the best
Jeff