Service hours provided vs available in Zoho Desk

Service hours provided vs available in Zoho Desk

Hi,

The use case is the next:

A company sells service hours, for example sells to 10 hours of "X" service of service, I mean the customer has 10 hours available to request "X" service, the client generates requests, the agents attend them and record the time entry that corresponds.

And the question is:

How, using Zoho Desk, the company could keep track of the available time that the client has vs the one he has used?