Hi Puru,
For Sales Orders:
You could try the method, First keep the accrual method to 'CONTINUE TO DEFER' and when you receive the payments then you may decide to recognize the revenue and since the payment amount is not fixed, now change the accrual method to 'RECOGNIZE BASED ON MANUAL AMOUNTS here you can manually enter recognized costs & revenues.
For Contracts:
Usually for contracts we have accrual methods like
1. Straight-Line -Exact Days
2. Straight-Line -Even Periods
These methods distribute revenue based on day / periods.
Thanks
Lokesh Sharma