The annual service charge budget is built from the rate per square foot for every unit you hold, and the real invoices and receipts sit beside it period by period. The two are kept apart on purpose: one is a plan, the other is what was billed.

Each project carries a service charge rate per square foot. Multiplied by a unit's area it gives that unit's annual charge, and a monthly figure with it. Where a unit has its own agreed amount, that override is used instead and the row says so, so an exception stays visible rather than disappearing into an average.

A real invoice is a period on the unit with its own dates, amount, due date and paid flag. The invoice and the receipt are attached to it in private storage, and a receipt may only exist on a period marked paid — proof of payment cannot sit on something unpaid.

A period past its due date raises a high-priority overdue alert naming the number of days. A period approaching raises alerts at thirty, fifteen, ten, five, three, two and one day. A period whose dates have ended without a due date being set raises a quieter unbilled alert, which is the one that otherwise goes unnoticed for a year.

No. A service charge is an owner-side cost, and tenants are excluded from it in the database rather than in the interface.
The demo opens instantly, in the role this workflow belongs to, on sample data. There is no account to create and no form in front of it.