Getting a payment and keeping track of which invoice the payment is received against, is complex stuff to manage. A customer may make a partial payment pay partial invoice, or pay an invoice in advance. The payment can be received through the bank or as cash. There are many combinations of the payment processing system. Odoo is capable of managing all such business cases out of the box using the Bank or Cash statement.
Let's see how easy it is to manage the statement; for the bank or cash. Create a statement, encode the entries, match the statement with the bank or cash balance, reconcile the entries with the outstanding, and close the statement at the end.