Everyone who owes you money, one row per customer with the oldest debt first: what they owe, how long it has waited, Pay, Remind and Write off for each job, Pay for all jobs for a customer who owes on several, and reminders, statements, documents and the debt list for the customers you tick.
How to print the debts list, or just the debts you tick, to take out collecting, with a box to tick when a customer pays in full or in part and room to write the amount.
How the invoice picker works from Record payment and the write-off popup: choosing the invoices a payment pays or the one a write-off is against, searching, and adding a new invoice.
How to record cash, a bank transfer or any other payment taken by hand with Record payment: where it opens, what each field does, how it pays invoices, paying for all of a customer's jobs at once, and sending a receipt.