I have a half built new version of the 6x17 in the garage now that has bellows, ground glass and a much improved film transport (Mamiya parts extended to 6x17). It has cost me so far about $150 not including the lens, and that 150 includes a lot of dead ends and frustrating nights and also building it out of some really nice walnut...
The main design issue for building a camera like this is light--- keeping it out, keeping flare down inside the camera, and always photographing with the light behind you. Once you can understand that light does not go around corners and that anything can be made "light tight" with a liberal dose of gaffers tape, you can make really neat cameras. This camera is about the 50th one I have made--- only the third or so panoramic camera. Many of my cameras have not had more than a single roll or a single frame taken with them. Many are experiments and ideas and as I say, dead ends and one too many beers in a weekend sort of cameras. (like the three shutter contraption I attempted to make... )
With the simplest tools vise, file, hacksaw, drill, tap, you too can make something like this. All it takes is desire. cameras like this are so basic and simple, by the end of construction you feel ready to make a dozen more.
All this camera is is a box. There is no focus mechanism, there are no complicated mechanical bits. The lens is at a precise point where at f22 everything from 15 feet or so all the way out to infinity is in focus. The entire procedure to take a photo is to make it level, then sight down a couple lines I have drawn to get the horizon level and to get the meat of what you want centered in the photo roughly centered. set shutter... step back and click.