The thing is that I’m not really interested in selling membership levels, but for example if I want to charge a $5 monthly subscription fee to members (any membership level) for joining a Group and a member wants to join two Groups. How can he/she pay for that?
So in this case the product would be Group monthly subscription, not a Membership level.
Hello. Current version of Groups app allows to use Paid Join. Group creator/admin may add pricing options for his group and users would need to pay before join. Each group may have its own pricing options, for example, Group 1 may sell monthly subscription for $10 while Group 2 will sell monthly subscription for $5. In this situation we have different groups with the same durations and it's not the same as "to sell 1 month of a Premium membership for $10 and for $100".