Two ways to setup paid listings.
Option 1 - Users pay for each listing with a listing credit for a specific category
Option 2 - Listing Credit Packages - Users buy credits which can be used in any category and just deducted from the total.
I have now managed to setup using the credit system.
But how do you setup paid classifieds without using the credit system, so that the user can pay using Paypal without having to buy credits?