You probably could do that, but I would have thought mail merge would have been more appropriate.
If you can manage with a subject of "Please find attached your invoice ####", with the #### filled from a field in your data source and the 3-4 fields in the message body and the path of the attachment also listed in your data source then
https://www.gmayor.com/email_merge_addin.html should be able to manage that.