Project Milestone - Customer Invoice & Revenue recognition

Dear Experts,

I got below requirement from client. Can anybody suggest, how to resolve this issue?

Scenario:

Project Milestone: Project team is coordinating the Project work & based on defined Milestone they are confirming the Milestone.

Customer Invoice: Based on the Company-Client agreement Finance team is Invoicing the Customer at different interval of time (Which is not as per project Milestone).

Customer Advance – Company is taking 30-50% of Advance from Client & want to recognise over a period of time (Maybe 3/6/9 months in equal amounts or certain Percentage for each Milestone).

Customer PO vs Sales Order value – Certain cases where Company has overbilled Customer as there is not validation of comparing Customer PO value & consolidated SO or Invoice value.

If we look at the above process, they are working independently in system & tracking of project to know current milestone, amount invoiced to customer & advance recognised are manual efforts. Hence they wanted to fix this.

Appreicate your inputs on this.

Best Regards,

Avinash