@Kirby @PinochetsCommieCopter Some breeds are okay and more ambivalent about sharing a pen, more wild strains can be pretty violent. You can generally have a comfortable ratio, I think 1:3 is a little excessive for most chickens, we were at 1:7 last year and at least 85% or so were fertile.
You can often buy birds on ‘sale’ from online breeders, but be ready for plenty of dead ones if you have a big temp diff. or poor post office handling. But going that way in the start gives you a motley assortment to sample and assess before going all-in on some show breed like people wanna do