[Invoices] shows all lots that have been invoiced. If a user purchased more than one lot in an auction each lot will be listed individually with the same invoice number alongside.
From this table you can generate the invoice in PDF format. Select the invoice you are looking to generate - if more than one lot appeared on that invoice they will all be automatically selected - then click on [Output (PDF)].
You can also click on the invoice number to navigate to the invoice for further editing.
See Post Auction Management for more information on invoicing.