Cost/Event or Event/Event?

Dear All,

We have to find out which extension to customize/use standard to achieve revenue accrual calculation to suit our business needs.

A)Please suggest should we use percent spent (cost/event) or Event/Event extension.

Here is our logic, thanks for reading in advance.

     A1) If Contract total is > 1 Million then it is "ClassP" project, else it is "class NP" project.

          For "ClassP" project, we will assess a risk % and add it to original baselined cost budget, which usually increases cost budget from previous baseline.

               We call it "Revised cost budgetP"
  

          For class NP project, no change in original baselined budget.