The po is generated. It is important that you document your new SAP contract or purchase order number, as vendors will have to add this number to all future invoices.Create the purchase order. If there is a purchase requisition, use it as a reference ( in Purchasing : Purchase order Create) For more information, contact the RFP Contact no later than ten (10) days prior to the Deadline for Proposals. 9 is required so that a vendor can be established in the County's financial enterprise system (SAP). The department requesting the W-9 will have the vendor.