Costing for Alternative Parts

Dear Expert,

There is a requirement for costing run with BOM which contains alternative parts.

For example, in CA01, BOM is maintain as such,

Part A which is quantity 1 pcs, alternative item group B, priority 1, usage probability 50%

Part A-1 which is quantity 1 pcs, alternative item group B, priority 1, usage probability 50%

when explode the BOM using CS12 and during running of backflush,

Part A shows 0.5 pcs

Part A-1 shows 0.5 pcs

However, for cost estimate,

Part A shows 1 pcs with cost RM 1

Part A-1 shows 1 pcs with cost RM 1.5

and the cost had been encounter twice (total = RM 2.5) where this is incorrect.

It should be as following:

Part A shows 0.5 pcs with cost RM 1

Part A-1 shows 0.5 pcs with cost RM 1.5

and total cost = RM 1.25

I had searched through the forum, most of the forums recommend on mixed costing.

However, this will require to maintain 2 BOM, 2 production version and some configurations.

Is there any other way to run 1 cost estimate which is able to pick up the ratio just like backflush?