AP pop up note for a job

We have a job (T&M) with one of our clients where they are requiring us to submit copies of all material invoices when we bill.  Is there a way in AP 4.2 to have a notice pop up when we input AP for a specific job? We have the ability to have alerts pop up per client when we are inputting service work orders.  So, we were hoping we could have something similar for AP on this project.  Our other option is a post it note on my desk to remind me to make a copy when I am inputting an AP invoice for that project.  Which is not a very efficient system.