Hi 

We are IT company for SMB's. We deliver services and we sell contract with Hours.

For example, a customer can buy us 20 H/year or 40Hours / years.

We manage contracts as projects in zoho book. Then we create a project with 40 hours.

Each time a engineer goes to the custormer for maintenance, he input time in the project in zoho to debit the project.

But in our contracts time from ticket should be debitted to the contract to.

For example, if this customer has an issue and a ticket is created, when the ticket is closed, we input the total time into zoho project related to this contract.

What could you suggest to do this the easiest way?

This way we can edit report with 

Total time for the contract

Remaining time and all action on project.

Thanks