OPEN BUILD TOWN IDEA

This would be a town where anyone could come and build on it, it would be like 20 or so plots large with a few rules applied and a system where you would have to be verified to get in. I have ran into a few issues with my plan, and needed some help on fixing it to work.
1: What would I set the perms as to prevent randoms from building on it?
1a: if I could permit randoms to build on it. Could I prevent griefing? i.e. TNT, Nether Stars, and Lava Casting
1b: If I added people to my friends list as a way to verify each person could I restrict my other plots (Embassies, Shops, etc.) to prevent them from building on it?
1c: If someone were to grief is there a reliable way of figuring out who did it by myself without bothering staff?
2: Would anyone be interested?

I will update as I get answers and as I figure things out. I really don't have the money for it right now I just wanted to iron things out before I decide to go for it.

 

You can set permissions per plot that you own

No, the only reliable method is through staff tools.