I originally built for 6. I now have 51! It's a sickness!!!Chicken Math..... you build for three hens and you wind up with six.... Always double your estimate of capacity.....and your lack of self control when you go to the feedstore....
I had a pretty good mentor when I jumped in.... Dad turned his back on farming but he came away with all the stuff his dad taught him.
One of the best advice is not to Anthropomorphize. like "Omg my hen hates me because she wont come near me" Or one hen chases another pulling out feathers shes bullying.... That's pretty much chicken life.... Hen pecking and hierarchy... Normal squabbles..
Good luck and have lots of fun.
deb