You should be able to use 1 2.8mm camera at the front door. I would recommend putting it in the right corner, if you are looking at the drawing. I would also recommend criss crossing the two cameras on the garage so that you capture the entire driveway and the street from both directions. A camera facing back at the door may be a little overkill or should be left for the last camera if you are installing them all around the house. IT may be a good camera to keep an eye on your packages or to see if the door is open or closed. You might as well run a cable to that position since you are putting a camera nearby.