Suggestion for you...

I like that I can set different permission levels for players, but I'd like the ability to allow them to be able to decide how much protection they want. 
For example,

Level 1 -- 25% protection, x1 cost. 
Level 2 -- 50% protection, x2 cost. 
Level 3 -- 75% protection, x4 cost.
Level 4 -- 100% protection, x8 cost. 

Would this be feasible?