An automated purchasing method for buyers using a high volume database and a high volume software program that is compatible with SAP® business management software having an SAP material master database includes creating a new record upon having received a request for purchase of a new item, determining whether the new item is a high volume item, determining whether the new item has a matching entry in a high volume database, and either automatically or manually updating a purchasing info record and source list entry for the item. A requisition and purchase order for the new item may then be sent to a vendor. Optimized prices may be negotiated from the vendor based on documented records of the total items purchased from various respective manufacturers and vendors. Updates or discounts then applicable to the given purchase order are returned and updated in the high volume system such that those discounts and pricing updates are available for subsequent requests and purchases via the high volume program.