Hi, I'm new to raising chickens and currently have 4 (7 week old) pullets. I bought a coop at Big R but am worried about a few things.Please see all of my many questions below. Here is my coop. The inside area including the nesting boxes is 2'2" x 2'4". This includes the above nesting boxes and the roosts. Big R said this was large enough for 4 - 6 chickens, but now everything I have read says I need twice this amount. Is this large enough for my 4 chickens? The overall size including the run area within the coop is 6 1/2 ' x 2 1/2 '. Do I need to enclose that entire area? We plan on building a chicken run that will be around 5' x 12' so we could certainly enclose this if needed. My next question is about the ramp leading to their door. There is a doorway, but no cover. Do I need a locking cover on their door for nighttime? Last question is about venting. I've read that we need venting and this coop has none other than the door with no flap. Is this something we need to put in or do we not want vents in Colorado? I live in Colorado Springs, CO, so we do get snow and cold temps in the winter. Though not all winter long, just weeks here and there. Should we insulate it? I am not positive what breed of chicks I have, but think I have 2 buff orpingtons and 2 road island reds.