On each Line in the quote, the Sell price and hence Unit Sell Price is normally calculated as described in Line Charges.
There are occasions however where you may want to adjust or simply specify an alternative sell price. You can do so by double-clicking on a line's Sell or Unit Sell columns, which allows you to override or Fix the price.
When this is done, the Sell and Unit Sell values are highlighted in yellow to indicate that the price has been manually set, and the Adjustments row in the Quote totals is used to account for the manual changes:
In the above example, a single line item has had its price altered; the calculated sell was $1126.70, resulting in an adjustment of $73.30 in the final total.
To remove fixed prices, select the rows with fixed prices, right click and select Release Fixed Price from the context menu.
CAUTION A fixed prices is just that, fixed. Any changes to quantity etc will not modify the fixed Sell value. (In the above example the quantity is 40, changing this to 20 simply doubles the Unit sell to $60). Similarly any other changes to processing, material etc are all ignored when the sell is fixed. If substantial changes are made to a quote all fixed pricing should be released and the quote recalculated, then pricing can be re-fixed if desired.