Vendor Specific Cost Price

Products can be associated to multiple vendors with unique cost price.

By assigning multiple vendors on a product, each vendor may have its own Cost Price associated when making a Purchase Order.  The first vendor assigned is the primary vendor, by default.  However, you may still assign the Primary Vendor of your choice by checking the box for "Primary Vendor"

When creating a back order for the product [with multiple vendors], you may select the vendor to create the back order with.