How to make a paywall in una?

Now we have one click private site option to force people to sign in, but instead of just the sign up block I want to show the pricing tables and they must pay with paypal to join the site. I desperately need this and this will stop all those inactive accounts from taking up space and making the site look dead or spammed out. Along with the new pruning feature, the paywall is a must for premium sites to enforce quality control so it doesn’t end up to be something like Twitter. Twitter is full of junk because anyone can sign up for free. Especially for dating sites where people need to be serious about being a member of the site. How do I make a paywall in UNA?