We often have to sum up multiple invoice lines to code the total to one account. We would like to be able to highlight the lines that are coding to the same account so the approver can easily see what is being totaled in order to verify these calculations.

There is a draw and/or text tool available that we could use to accomplish this, but changes made on the invoice image with the draw tool do not save for others to view. I understand the desire to protect the integrity of the original invoice, but I think highlighting would allow us to identify these items without changing the underlying data.

This could also be accomplished by saving drawing/highlighting/text on the invoice, but automatically saving a copy of the original as an attachment (similar to the original email attachment) or in some other way allowing us to toggle between the edited and unedited versions of the invoice.