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To use these, the ‘Apply custom price’ must be selected:
Discount price: By using this option, and clicking ‘Save’, the 'custom price' entered takes effect on the quote at the desired price location and displays the amount of discount applied compared to the expected price from the inventory set up for the quote items.
Price override: Using this option and hitting ‘Save’, overrides the expected calculated price from the inventory set up for the quote and directly sets the custom price at the desired location.
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