There are 4 sub-tabs at the visit payment screen.  The purpose of these tabs is to allow users to easily see all invoices and payments

• Unpaid Client Inv Tab - shows all unpaid invoices for this client, these can be from current or previous visits or "non visit" invoices
• All Client Inv Tab - shows all client invoices, open/closed or paid or unpaid
• Visit Payment List - shows all the payments taken in the visit and the associated invoices it was applied too
• Invoice Payment List - shows all the invoices that have been paid in the visit and the associated payment(s)