Content writing site with payment gateway integration

I am looking for a small project. The basic functionality is: 1. User can view, but need to login to write stuff to the site 2. Simple input page with ability to mark posts as public / private 2.1 Public post will be visible to all 2.2 Private post will be visible to user 3. If user selects paid service, it should take him to checkout to paypal. 4. If user selects non paid, it will be public post and will be visible to all 5. Paypal integration for paid service Admin 1. Normal admin functionality to manage user and his posts