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A promotion may be a template of items - to allow quickly entering a standard order with 10 lines etc of these products etc.
A contract promotion is used for agreed pricing by SKU, be linked to one or many companies, or to a company group and can have active and expiry dates
Promotions may have a % that can be claimed from the supplier of the $ sale, $ cost, Volume etc. for supplier assisted promotions - like new product introductions.
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