In OneOfficeERP, Item's stock valuation is updated on the creation of one of the following transaction.
You can select valuation method based on which item's value will be calculated. Valuation Method can be set globally for all the items from the Stock Settings.
You can also set Valuation Method in the item master, especially when a valuation method for an item is different from the default Method as seen in the following screenshot.
Note that once ledger entries are made for an item, this option will no longer be visible in the Item form.
Click here to learn about the valuation methods available in the OneOfficeERP, and how it works.