The robotics components were the pricey part. The breakdown is something like this:

  - Table (w/ paint, wood, pipes, lights, etc): less than $50
  - Electronics (Raspi, camera, cables, electromagnet, microcontroller, etc): about $150
  - Robot arm (structural components + servos): $350

It's hard to say what I would do a second time around since there are aspects I still want to work on, I want to write my own chess engine for it!