Accounts receivable cockpit
Anything that needs billing should be visible here.
New Visit
Capture the work before you leave the customer.
Customers
Billing, tax and payment preferences.
Products / Services
Reusable line items; recurring agreements still keep their own price snapshot.
Invoices
Draft, sent, partially paid, paid and past-due balances.
Recurring Billing
Automatic invoice generation should never depend on memory.
Configuration
Installation-specific values belong here, not in source code.