Ok..I am lost...

I have a client that supplies mortgage broker leads to those that sign up for their service. Each person choses what states they want to view leads for when they purchase the service. I need to be able to set it up so that once that person logs in, they are only allowed access to the leads for the states that they chose when they purchased the service. I am at a total loss as to what the best way to do this is. Does anyone have any suggestions??