ERP
Double-entry books, stock and the work around them, kept next to the record of the money that actually moved through Pay, so the accountant and the payments team read the same numbers.
Two ledgers, on purpose
ERP records what is owed and Pay records what moved. They are reconciled, never merged.
A month you can close
A closed month takes no new postings.
Stock at cost
Stock on the shelf and its cost, in the same system as the invoice.
One platform, not a stack of subscriptions
ERP shares its customers, domains, team and bill with everything else here. Nothing is re-entered, and turning it on does not mean another login for anybody.