The only work involved was spraypainting an empty roll tube. With care, the cardboard tube will last indefinitely but I plan to find rigid plastic tubing with the correct inside diameter. You'll definitely want to do so if you own heavier watches.
As a bonus, the inside of the tube is ideal for storing extra watchbands, pins, etc.
Width of the rack gives room for about 7 watches, if you're a different-watch-every-day kind of person.
Total construction time: 20 minutes waiting for paint to dry; 30 seconds screwing rack to the wall.
PS Yeah, my watches are junk.