I am thinking of purchasing 8 chicks soon. 2 barred rocks, 2 astralorps, 2 buff orpingtons, 2 of whatever else I find at tractor supply. What size should the coop and run be? They cant free range since we have a dog that would likely make them a snack. I will make a portable space for them to forage in addition to their run. My thoughts were a 4x8' coop and a 8x15 ft run since it will be against one side of our fenced garden. Is that sufficient?