Has anyone here actually built a boat from scratch, either from plans or from a kit?

This isn't something I'm seriously considering for myself, I'm good with my hands and probably could do it. I'd build a scale model first though, which I might do anyway. But I think a full size boat may prove to turn into a long and expensive project, expensive compared to buying a second hand boat of similar size. Which is around the 20 foot mark, for cruising, day sailing.

If you have any experience or perhaps some plans you'd like to share.....?