[sg999]

I'm not sure if this will help you, but I remember seeing a rather avant garde cart at the NYC regional last year. It was essentially a low-ish store bought tool chest with wood blocks fixed onto it to prop the robot up and handlebars. Now, as to the 4 castors vs. 2 fixed 2 steering arguement, we've recently been using 4 castors. We do have an older robot cart that has 2 fixed and 2 steering wheels, but even getting it out of our storage area is a huge hassle, so if you can, try for 4 castors. The cart moving on us has never really been a problem, as there's usually something lying around we can use as brakes. That said, our old robot cart is also on the chunkier side, while our current robot cart is more minimalist.