You can view Invoices and Work Orders associated with a Customer on the history tab. You can do so by following the simple steps shown below.

1.  Select the Customers icon in the menu ribbon on any page.

2.  Select the desired Customer Record.

3.  Select the Timeline tab 

4.  You can toggle either the Invoices or Work Orders.  The default view will display both.

5.  Select one of the timeline records to see more details.