What about going with a warehouse and have everyone pitch in for interlocking rubber flooring? I set them up volunteering for a wheel chair games event, a little time time consuming but easy to do.
Lol, I was in posting limbo, while my kids were talking, so I second Lala's suggestion. The type we put down did not need to be anchored, they stayed put rather well.
I do that all the time)))))
I didn't know that existed. that's amazing and is a solution for sure. warehouse sounds like a perfect place