A visit invoice can be printed from a visit record at the "Invoice tab" as well as the "Reports Tab".   Client invoices can be printed from the client record invoice tab.  All invoices can be viewed at the client record but you will be prompted to go to the visit record to print.

There are two formats of printed invoice

For open invoices a "preliminary" invoice will be printed.  The preliminary invoice has a very distinctive look so as not to cause confusion for clients or staff (see below)

For closed invoices a "Final" invoice will be printed.  

A payment receipt which shows just the payments applied to a given invoice. A payment receipt can  be printed in the visit record or client record.