How do I use registrations for billing for something like a weekday preschool?

Step by step instructions on how to leverage groups and registrations to push out billing notifications with a payment link.

This question especially seems to arise with church's that need a streamlined way to manage monthly payments for something like a weekday preschool.  
  1. Create the Weekday Preschool Registration Group.
  2. Go to Registration then settings for the group.
    1. Set this up similar to how you would set up a VBS registration with this group being for parents and another group to register kids.  You'll manage the kids classes like attendance in these other age specific groups.
    2. Under Registration cost put in the full regular amount for one child
    3. Use Registration attributes to create a registration amount for additional children. This will include the amount for the additional child in the first payment and serve as a "reminder" in the group view for calculating future payments.
    4. Use this group for your initial registration.
  3. To use the payment reminder for future payments. 
    1. Review and manually note any unpaid amounts due listed for parents in the group.  You will add these back in to their next payment.
    2. If you have costs that accumulate between payments, you could also use a Registration Attribute as a "reminder" to track these until the next payment is due.
    3. Click Registration then Settings and click the red "Reset / Clear Registration" button, Save and Confirm.  This will get rid of the amounts paid and due.
    4. Click Registration then Settings and remove first then add in a new Registration Cost (per person), Save and Confirm.  If the amount is the same, you will have to clear it out by changing the cost to anything else and saving that first.  Then come back and follow the same process to change it back to the desired cost. This amount will now be registered as due for each parent in the group.
    5. Back in the group, use your manual notes and/or "reminder" Registration Attributes (items 1.3 and 2.2) to calculate additional payments due. Click Edit to adjust the cost. Now, your billing for the month is set up for each parent.
    6. Select all in the far left column, then click "Send Payment Reminder".  This will send each parent a payment reminder with their unique amount due and a link to pay that amount online.
  4. Any check or cash payments should be entered into the group using the green Pay button.