Pop Up Message before another workorder can be scheduled on a job/address/customer who has an open balance

If a customer has not paid an invoice or open balance past a certain grace period and the billing departments needs to make sure other departments know that other services or work should not be performed on that site or for that customer until payment is received. It would be nice for a pop up message or something that is eye catching would show to anyone who is trying to schedule a job for that customer or at that address.