Pay for Access Areas in WordPress

I want to build a wordpress site that shows some content to all, and then only shows the rest of the content to people who have paid either via paypal or credit card. Moreover, I want this access to happen automatically upon payment (if possible), i.e. I don’t have to manually give that person access after I check to make sure they have paid.

Is there a way to do this in wordpress or would something like rails/django be more appropriate?