This is a really cool idea. One of the first problems you'd probably have to overcome though would be insurance. For pilots there are very strict certifications

This is a really cool idea. One of the first problems you'd probably have to overcome though would be insurance. For pilots there are very strict certifications and strong personal incentives not to crash. With a modern Cnc machine it's very easy to cause more damage than you can afford to fix (if you can't afford the equipment in the first place) and you don't even have to put yourself in danger to do it.