Change Orders allow you to sell new equipment after a contract has already been finalized. You can use Change Orders to swap out equipment (upgrades and downgrades) or simply add new equipment and/or labor.
To replace any of the items in your project with new items:
Select your Change Order (or create a new one if you don't have one yet)
Click "+Add Items" to add the new items to the CO
On the Add/Edit Item modal, select "Replaces Existing Items That Are Already In This Project"
Select the item(s) that you would like to remove/replace
This will add a "Credits for Replaced Items" line on your Change Order Report, and give you a total upgrade/downgrade price.
Hope this helps - let us know if you have any questions!