if the item price changes (including subtotals) you have to manually change the quantity.  If you forget to do this the calculation does not change. How about an actual PECENT discount where the percent actually uses the line item changed price OR  subtotal changed price to automatically calculate the correct PERCENT discount amount ON THE FLY!  (Like the desktop version does) currently If you reduce the price after negotiations you must change the quantity Or you discount will be too much in some cases WAY WAY TOO MUCH.  Please get your act together Quickbooks Online.  The functionality must be in a product like yours.