Purchasing price variance measured against a budgeted price

Hi,

We'd like to be able to store a budgeted price, or a price that was estimated when calculating margins on a new product, and later on be able to compare the real purchase price (moving average) against that "budget price".

We initially used STPRS the standard price to store that "budget price", but we realized that when using MR21 to adjust a moving average price, the standard price is set to zero.

SAP offers purchasing price variance, but in this case, we don't want our initially estimated to be the standard price, as it would impact our cost rollups.

We could store this estimated price in classification but are wondering if there is a standard feature that would achieve this in SAP ?

Thanks!

Olivier.