Economic realities

Money makes the world go round

Purchasing Quantities

In general, the more you buy the cheaper each thing will be. A great example of this are the resistors you can buy on Digikey. The RC0402JR-0710KL resistors have the following price breakdown:

Counterintuitively, this means that buying 5 resistors ends up being more expensive than buying 100! For more expensive components (e.g., microcontrollers) the pricing structure is less extreme but the general trend remains. In the context of building and designing robots, this means that, to the extent possible, it is best to minimize the number of different components in your design so that the quantities of each component are maximized (this will also make assembling the PCB much much easier). When reporting robot costs for swarm robot papers, it is generally accepted practice to quote the cost of 1,000 robots.