OM bundled item ordering, line level discounts, and discounted drop ship purchase orders

Summary:

We have a business scenario where a supplier will provide us a cost break when fulfilling orders via drop ship if we sell a combination of certain products together. We want to sell this "bundle" of say 4 items (multiple size combination skus within each item) so that if a customer orders these 4 items together they would get a 15% discount. We would want to force all lines to go to a drop ship PO, where we would take an agree 25% discount in cost from our standard BPA price. We would want to support this