How to restrict users from changing unit selling price in an order line?

The Profile option “OM: Discounting Privileges” provides us an opportunity to restrict users from changing the price in sales orders.

 

The profile option has 4 values,

Full - Ability to apply any valid discount against an order or order line, as long as the order type of the order does not enforce list prices.

Non Overridable only - Ability to apply only non-overridable discounts against an order.

Unlimited - Ability to apply any valid discount against any order or order line, regardless of whether the order type of the order enforces list prices.

None - The user cannot update the selling price (view only access)

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