The component with the lowest price in the FRONT WHEEL (RM85LK3/LK4) schematic is the Pin 20x20.
Some items from this specific schematic: Disc,front Brake, Nut,m12x1.25x1, Rim,fr Wheel(1.40x19), Washer.
The Front Wheel (rm85lk3/lk4) assembly is constructed from several parts from which the Rim,fr Wheel(1.40x19) is the most expensive.