These costs are calculated based on buying the unfinished potion premade. This allows you to skip putting clean toadflaxes in a vial of water. However, this method is more expensive. The extra loss accumulated via this method is 443 per potion, however, the experience per hour is doubled.
The profit for making an unfinished toadflax potion using either a vial of water or filling your own vial is as follows.