Hello there, patrick-kennedy.
QuickBooks Online can print the invoices itself, it will not include the attachment. Thus, there is a different way in printing the attachments.
Then, when sending invoices to your auditor via large email, you'll have to go back to your invoices and make sure to enter your Auditor's email in the Customer email field.
Here are the steps:
Once done, you can go back to the Invoices tab and check the Invoice transaction boxes. Then, click the Batch action button and click Send invoices.
Please let me know if you have more questions.
Thanks however this only allows for batch printing of invoices and batch printing of attachments. What I would like to do is print the invoice and it's attachment as one file/PDF. At the end of the month (if I have 50 invoices and 50 attachments), I could then print each invoice with it's attachment and send in one email to the auditor (ie: 50 invoice+attachments = 2 PAGES each (100 pages total).