I built my own 55' tug style. Did it to my own plans and worked mainly at weekends and in fair weather. I did find it took longer than I originally estimated but then I did start a little late in life.
If I could turn back the clock I'd probably have done things differently, would likely have bought a sound boat that needed restoration and gone that way. Immensely satisfying but don't underestimate the amount of work.
The only other thing I'd say, as the majority of work is in the bow and stern, do think carefully about the wisdom of building a "short" boat.
A mid build photo...