The Last Cost represents the amount most recently paid for an Inventory item. It is used as the line item Cost when an item is entered on a Purchase Transaction and the Vendor Cost is unavailable, unless the the Load Cost From Line Item Entry Parameter is set to Last Cost in which case it is always used.
The Last Cost field is updated automatically whenever the Quantity On Hand is increased when Receiving items in Purchase Manager, Accepting returned items in Sales Manager, and using Automatic Case Break-Downs unless the Update Last Cost Update Parameter is disabled in Purchase Manager in which case the Last Cost is not updated.
Note: When adding new Inventory records, the Average Cost amount is automatically copied to the Last Cost field to ensure that a Last Cost is entered on new items. This action is controlled by the Field Links specified in the Default function and may be changed as needed.
Inventory Database - Main Screen Fields