I have no chickens yet, but I'm preparing. I want a chicken tractor in my fenced garden. I am thinking about 3x3x8 for 6-8 laying hens. I can grow greenery all year long for them to eat, but will they be happy/warm? Or should I move them to a coop with a fixed run or something? How easy is it to move chickens from tractor to coop and back again--70 degree days in January are not unheard of here. I read the book "Chicken Tractor" by Andy Lee but it seems to reference using one for broilers in the summer. I have land, and I want to give them the most room for movement/greenery while keeping them safe & happy. Thanks!