Many, many, many years ago I got a Bender kit, Don't know what i was thinking as i really didn't have the tools to keep everything square. love building things with my hands but it takes more than that. Got a couple of clamps and then decided that by the time i bought the necessary tools I could have had a camera ready built.
Luckily i sold the kit and so there was nothing loss.
If you had the tools, patience and like working with your hands I would go for it.
There is a shop in town that does a workshop on building a 4 x5 pinhole camera, and I am always tempted to sign up, but I already have too many cameras including a pinhole that hasn't seen the light of day since last year some time. SO.........