Hi! I am planning on building a chicken tractor type of coop. Right now I have 2 birds, a banty rooster and a guinea bird. I plan on adding 2 banty hens with them. I will be building a 4x8 run with a 4x4 coop ontop of the run with a ramp leading down from the floor of the coop. Will this be big enough for them? I was hoping it would since they are just bantys.