I have an XC MTB, a road bike and a trainer, which I maintain. I also do maintenance for the kids and wife's bikes.
Today I replaced a cassette in my road bike - something that required special tools but was rather easy.
I think I might be ready for the next level - to put a whole bike together.
I'm thinking a single speed (freewheel or switchable) would be the easiest to build, perhaps with a front brake only - get a frame, ready made wheels, hubs, chain, sprockets etc and I should be good to go?
Am I being too optimistic? What it the hardest part of building a bicycle?