Hello a good compromise is getting a round one (without the net) because they are evenly tensioned all the way around, the kids don't seem to bounce right off the edge like they do with a rectangular one. Also, strictly enforce the one bouncer at a time rule, and you will need to supervise her carefully for a couple of years anyway!

I think it's a great idea and DD bounced happily for years on other ppls trampolines without incident!
:-)