Billing built around how Kumon parents actually pay

Maria has Diego in Math and Sophia in Math + English. Old way: 3 invoices to track, 3 reminders if she misses. Kumon Ops generates ONE consolidated invoice per parent per month with line items per child per subject. Tracks paid / unpaid at the parent level, where it actually matters.

Set a sibling discount once at the franchise level (e.g., 5% off second child, 10% off third). When you add a sibling enrollment, the discount auto-applies. Update the discount rate and historical invoices stay locked at their original rate - no retroactive surprises.

One click generates a hosted PayMongo checkout link. Parent gets a Messenger link, taps it, pays with whatever method. Webhook drops the invoice to Paid the moment PayMongo confirms. No 'I sent it na, ate' screenshots to verify.

If you pass PayMongo's processor fee through to the parent, the fee shows as a separate line on the invoice AND on the PayMongo checkout description. Parents see exactly what they're paying for. No hidden inflation.

One-time enrollment fee tracked apart from monthly tuition. Roll-up reporting separates 'registration revenue' from 'monthly recurring' - useful for understanding new-enrolment trends vs. baseline.

Diego enrolls on the 17th. Kumon Ops bills him for the remaining 14/30 of the month at his subject rate. No back-of-envelope arithmetic.

Parent pays ₱3,000 of a ₱4,500 invoice. Invoice flips to 'partial'. Balance ₱1,500 carries on the dashboard until settled. No special-case workflow.

Every list view exports clean CSV (UTF-8 BOM, formula-injection guard). Print view strips chrome and renders the invoice on A4 for parents who want paper copies.