To carry on Francisoco's suggestion, you do not have to Drop Ship the Items. You could also have the Items sent to you prior to going to the Customer. You would still use a default Vendor on your Item card. You would also need to establish a Reordering Policy for the Items (they can each have their own type of replenishment policy). After the Items are setup, you would use the Planning Worksheet to Calc. a Regenerative Plan.
The Planning Worksheet reviews all the Supply and Demand for the Items with Reordering Policies, then makes suggestions on what to buy/make/transfer based on how each Item (SKU) is configured.
There is a lot of flexibility in the replenishment system, so I strongly encourage you to reach out to your Microsoft partner for some training on the available options.
