Invoices is an umbrella label for the payment system introduced in the Fall of 2019. It is intended to unify payment administration for registration, team payments, event payments, and general-purpose, one-off fee collections. 

An invoice defines most of the essential ingredients of a payment, much like a game slot does for a game: it won't 'do anything' until it's been matched up to one or more invoice payers, but it enables you to group 'like' transactions. Invoices contain high-level information about an amount owed that is common to every payer:

• Invoice label, or short name
• Invoice description (for all payers)
• Amount due (prior to discounts)
• Contact email
• Merchant account to process payments
• Season relevant to the invoice
• Optional payment schedules