The best way to determine placement is to buy one varifocal camera, build a test rig as described in the WikiCliff Notes or use a step ladder with an eight foot 2x4 clamped to it to mount the camera to, and test each location. Testing means leave it there for at least a day and have someone walk by playing bad guy, both during the day and at night, to see if you can really identify them well enough for the video to be used as evidence by the police or in court. The varifocal lets you adjust the focal length so you can get the right lens size for each location.
You know what you want to cover, or should be thinking that through, so no one can say put a camera here. Not testing is a road to poor choices and useless cameras.