Add a “Price Updated” Date Filed and a field to keep track of the user that updated the price to the Item Form. Then have the system warn you when you add an item to an Form like Invoice, Estimate, PO etc. if the date is beyond user defined date range in the preferences. (preference could be turned on or off as desired)
I have over 23,000 items in my system. Keeping the item prices up to date is always a struggle. Having a preference like this would help us manage selling items with an outdated price.