Internal cost estimating?

Internal cost estimating?

I'm not sure where to ask this question. We use ZohoCRM and are, for the most part, quite happy with it. We have a need to do internal cost estimates, I'm sure there's an official term for it, but basically I'm looking to create some kind of internal invoice showing what the costs related to each customer are. Is there a tool like this somewhere in Zoho's library, or does someone have another suggestion?