Our memberships run on the calendar year. So if someone joins on 7/5, we give them that month for free and prorate by month, so the first payment on 7/5 would be for Aug and Sept, then the second installment on 9/20 (whatever date we set) would be for the last quarter.
If they join on 8/26 we would not want to bill for 1 month. We would want to charge for Sept 1 - Dec 31 . Having a selection to allow a minimum amount of time to bill for would be very effective.
all our memberships expire on either 6/30 or 12/31 depending what the members chooses for a membership, 6 mo or 1 yr
Monthly installments we would charge the day they sign up for the next month(not the month the joined) and always charge on the 1st of the month.
We have semi-annual and annual memberships that all run from 1/1 to 6/30 and 7/1 to 12/31
Installments need to always be on a specific date. if a member renews on 12/10/16 for a year and does 2 payments we would like to set the date for the 2nd payment on 6/20 (or whatever we choose)
If someone joins on 3/5: we give them the first month for free and prorate by month for either 3 months or 9 month depending on how long they want to join for. if they join for 9 months have the second payment due at the 6 month mark 6/20.
It would be good to be able to calculate prorating by day(the way it is now) or by month.
This way a member can actual understand what the calculation is and it keeps thing very simple.
This also rolls into deferred income: if they renew on 12/16 then the income would need to be deferred till Jan 1 of the next year.