I have seen this done in the back of a covered trailer. The guy had his machine bolted to the floor of the trailer and had chairs on the side. I think it was about a 3x5' machine. This was at a crafts show and he would vcarve your kids names in various plaques that were ready to go except for the engraving which only takes a few minutes. I sometimes travel up to Northern Michigan to the Buckley Old Steam Engine show, an amazing event. Several years back another guy did the same thing. He had a small Honda generator for power.
https://www.google.com/#q=michigan%2...72858744415716