In an area like VT, I would definitely go with 4 sq. ft. per bird. So a 3 x 4 dog house...three of the breeds you mentioned. Keep in mind that a nest box inside will take up living space in the winter time, as you only want them in it for laying eggs. A big 4 x 4 dog house...four birds. If it's a little less than either mentioned, I would go with one less chicken than mentioned. Of course the run would need to be a little more than double the size of the coop housing. If you don't insulate, you can stack hay bales around the sides of the coop to help w/winter insulation...