How can I override the prices of an item on a project?

Let's say you want to charge a client a different price for an item.
You can click the three dots next to the item and click 'Edit'
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Next, click 'Override Amount'
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Then, enter in the price you want to charge your client and click 'Save'

Finally, this update will be recorded in the Logs for your reference with the original price and the overridden price.