Step 10: Boundaries
Boundaries are important. Ideally, the wheelchairs will be completely fenced off with sturdy chain link. A tennis court with no net would be ideal. So would a bumper car court.
We made wood-and-rope boundaries, and they didn't help at all. They're just a piece of 4x4 on a plywood base and an eye hook screwed in to hold a rope.
Do something better and more effective, because the wheelchairs will hit the boundaries on a regular basis.