Hi,

In Odoo 19, extra prices set on product variants are applied per unit of measure (UoM), meaning the system multiplies the surcharge by the quantity sold. Unfortunately, Odoo does not provide a native option to apply a fixed surcharge per sales order line that is independent of the UoM or quantity.

A practical workaround is to create a separate service product, such as Cutting Charge, with a fixed price (e.g., €10). This product can be automatically added as a new line in the sales order whenever the “Cutting Required = Yes” attribute is selected. Another option is to make a small customization by extending the sale.order.line model and adjusting the price computation to add a fixed surcharge when the “Cutting Required” variant is chosen.

If using Odoo’s Product Configurator, it’s also possible to modify the configuration templates to support fixed extra costs. In short, while Odoo doesn’t natively support fixed surcharges per line, it can be implemented easily with a light customization or by adding an automatic “Cutting Charge” product line.

Hope it helps

Define a Product Warning reminding people to add a separate Cutting Service.

Enable this option in Sales --> Configuration --> Settings:

Look for the section named "Warning on Sales Orders" at the bottom of the Sales Tab on the Product.

When it is added to a Sales Order, the Waning will show at the top: