The Payment addon for UserPro lets you create paid memberships on your site.

This version of Payment addon is fully integrated with PayPal, 2Checkout, Authorize.Net and Stripe.

How does this work?
With this addon, you can now make people pay for registering on your site. After a user fills up the registration form, he/she will be directed to PayPal or Stripe for making the payment. Logging into an account is only possible after the payment is successfully received.

If a user registers but does not pay, his account will show up under the “Admin Approval” screen. You can choose to manually approve / enable these users if you want to make an exception.