I built something similar many years ago.
It worked OK. It did not go as well on the beach as I'd hoped. What seems like hard sand is not so hard under wheel.
The hardest thing is finding an open area with a bit of wind.
BItumen offers the least rolling resistance, but tends to be long and narrow and populated with weird metal boxes on wheels that think they own it.
I did see some netball courts that looked promising last year.
nebbian said...Man now you're making me scared.
I just sorted out something along the lines of this:
and am all

in anticipation...
So private health insurance is the go?