I was fighting this also. I usually keep around 12 hens in a 64 sq. ft. coop. I ordered 6 blue wyandottes from the feed store, planning on keeping 1/2 my 2 year olds & the 6 new. Now I have reconsidered & picked up 8 instead of 6 & will probably move the 13 2 year olds on. That way I can finally add 4 or so next year & have laying staggered. I usually get all new, but miss the eggs over the summer. 8 should give me enough eggs next year with maybe a few to give away. Depends on who I find to take my old ones.