In the world of hobby-level CNC cost and simplicity are usually the name of the game. Using inexpensive and easily found materials makes a big difference in the feasibility of a project.
[Petteri Aimonen] demonstrates three inexpensive ways to DIY some bellows-style dust covers ... and this limits how close to the end of travel the CNC carriage can move with the bellows attached.
Solar panels can save money or increase energy independence. If you want further savings, you can DIY solar panels, which requires more research and effort but can result in a cheaper system overall.