If you have power and line of sight to a building with Internet (or a NVR), you can do a point to point wifi radio like a Uniquiti Nanobeam and support the cameras that way. Most cameras rated for outdoor use (IP67, etc.) and shouldn't need a housing.
Set static IPs on all the cameras. You can preconfigure them individually with 12v and a patch cable to a computer one at a time without dealing with a switch.