We did not choose a particular case for this project since there are so many different ones on the market. As long as you can accommodate and cool your components, it is up to you which model you want and how you want to customize it (if at all). You will get a chassis with sufficient ventilation options and drive bays for as little as $40 and we recommend spending some time on the manufacturer Websites after studying the price lists of your favorite e-tailer.
It's somewhat difficult to find the right PSU. You can get a 300-W power supply for as little as $20, and these might even work for our system. However, as we intended to build a machine that can last at least 18 months, we couldn't go for something that basic. We picked a Coolmax V500, which has a large-diameter fan