We used to have a big cart. It was difficult to move around in tight spaces and very expensive to ship to Atlanta. We now have an "I" shaped cart made out of 2"x6" aluminum extrusions with 30" handles on each end that can be reversed to make the cart a table in the pits or folded to slip the cart into the back seat of a car. It has four heavy castors and handles easily in tight spaces. The robot sits only about 6" off the floor so it is very stable. The cart is only 28" wide so it easily fits through doors to demonstrations. It is has room for four batteries or two batteries and some tools on the ends.
Link to our cart