Hi Chris,
This is a good idea and certainly describes functionality that we don't have at the moment. This relates to a few different requests that we have had for greater support especially for those in the contractor industry who have different needs when it comes to purchasing and dealing with different types of transaction.
To be honest with you, this isn't something we are looking at for now but we are aiming to make changes throughout the app to support those in the building trade to reflect the requests we have had.
Hopefully your request will gather more votes as those similar to it have already done.