Enable an Attachment for Accounts Receivable (invoices to be sent)
Attachments (one actually) are permitted for Receipts and Accounts Payable. They would also be very useful for Accounts Receivable (invoices to be sent to customers).
Common attachments to be emailed with the Invoice are timesheets, quotes, and copies of acceptance certificates.
Attachments help getting the customer to approve an invoice, in turn helping to get the cash back faster.
This morning’s API release has extended support of attachments (file) to accounts receivable (sales) invoices: http://developer.xero.com/documentation/api/v2-release-notes/#2.31