The component with the lowest price in the REAR FENDER schematic is the Nut,flange,6mm.
Of all the components used in this assembly the Fender,rr.*nh138* is the most expensive.
Some items from this specific schematic: Bolt,flange 6mm, Fender,rr.*nh138*, Nut,flange,6mm, Protector Harnes.