Understanding the usage of Purchasing info records
Before a purchase order can be created in the SAP system, the prices should be maintained using Purchasing info records in the SAP system. Therefore whenever you purchase the items from a new vendor, it should contain the purchasing info records. The info records also holds other information which are related to the material and vendors for whom the info records are created. This data would automatically default whenever a new purchasing document is created using the Purchasing requisition or whenever the purchasing document is created directly.
Purchasing Info records will suggest different vendors to check price comparisons when multiple source of supply is available for the materials. Every purchasing info record is updated with the last price which was paid when the invoicing takes place.
Check this document on info record creation which contains the instruction with screenshots on creating purchasing info record.