An invoice with no property identifier cannot be coded by anyone but the person who ordered the work. Requiring seven fields removes most exception handling.
High volume, low variance, hard due dates, and an approval chain that adds nothing. Utilities are the clearest case for routing around your own workflow.
Payment redirection fraud does not need a forged invoice. It needs one email asking to update banking details, arriving at a moment when a callback feels excessive.
Three rails, three settlement times, three fee structures. The right one depends on the vendor, and paying everyone the same way is what makes vendors call your AP team.