How to define and apply procedures on Billing Extension?

Summary:

Hi,

We have a unique project requirement where the customer is invoiced only when the supplier sends his invoice to the business. The supplier invoice will have projects details and the customer details (in DFF or enable additional cost collection fields. ). We want to create and use a custom package to drive the customer invoicing. How can this be achieved? The invoice amount has to be derived programmatically and not from Bill Rates.

Thanks

Atul

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