Block Hours in Client Portal

We have quite a few clients that utilize block hours with us and it would be great if they could view a tally of their time purchased and remaining in the client portal. For example, if they purchased 40 hours and techs closed tickets totaling 16 hours, the remaining 24 hours would display for them along with the relevant tickets that resulted in the deduction. This provides an easy to understand real-time counter for them. Eventually, they would run low on hours and purchase another block to replenish their time with us.