Landed costing including third party freight vendor

In either AX 2009 or AX2012, we have a need to include the cost of a third party freight vendor on a purchase order and add it to the cost of the inventory received.  For example, we purchase a product from Company A but we will pay Company B for the freight to ship it to us.  We need to include the cost of this freight in the landed cost of the item purchased but pay both Company A and Company B from the same purchase order.  To complicate matters, occasionally the vendors currencies are not the same.  Has anyone done this?  And if yes, how?  Thanks for your input.