Vendor Monthly Subscriptions

This is not supported by EDD, but I was wondering if anyone has a way to charge vendors a monthly fee in order to post products.

I found someone who created an application form that accepts payment, creates the EDD subscription, creates the user, and sets the role. Any suggestions how to do this? This is what I am referring to: https://whiteleydesigns.com/modify-user-role-easy-digital-downloads-edd-subscription-cancelled/