quota

Hello,

Still a bit new to Rules, but I have been looking around and checking the documentation and API for the solution to my problem; still, I am quite lost as to where to begin, how to proceed.

So, all I want is to restrict, for a particular user role, the creation of nodes of a particular content type, by a quota. I want to count how many nodes of that type the user currently has. And say, that the maximum amount allowed for that user is 5, and he/she already has 5 nodes of that type when he/she tries to create a new one, negate the creation of the node.