POS Enhancement Requests

II have multiple House Account Clients that are requesting to receive their emailed invoice in a PDF Format. I can currently set up my register to Print out invoices in a PDF Format but when the invoices are emailed it is sent in the Default Invoice Format. I have over 55 House Account Clients that have requested their invoice to be emailed. I hate to think of the amount of time it would take to Open their account, reprint. save in a file, and then go to my email and individually email each invoice. I have some clients that have service weekly. Help save my sanity!