Time Accounting billed/unbilled

Hi,

I am Just Searching for the “perfect” helpdesk Software.

Zammad is really near to, but I have a few Things that I am missing and I dont know If i Just understood Things wrong.

First the time Accounting: I would have a Lot entrys for a lot customers. Some customers get an invoice at the end of the Month. There, the time Accounting is very useful. Just Export to Excel and bill them.

Some customers b2c should get an invoice right after finishing the Ticket. In this case, there is No Overview of what was billed. The workaround: finishing billed Tickets with a negative time entry so the customers have 0 Units.

If i do that, i lose the View on how much my employees have worked for their Money.

If i Just could diverse in billed and unbilled Services, zammad would be the perfect system.

But this way, I dont see much use in the time Accounting.

What could I so? What is already done? Could I use another time Accounting that can be integrated in zammad?