I'm quoting a 6 camera system and want to get some feedback on the best way to configure it.  The cabin where the NVR will go is 175 feet from the barn.  The barn needs two internal (IPOB-TP2MPIR50-W) and two external cameras (IPOB-TP2MPIR150L2812-B).  The cabin just needs two internal (IPOD-TP2MPIR50-W).  I've picked a closet (climate controlled in cabin) where the NVR (NVR-ELC-16-POE16) will go and plan on digging a trench between the cabin and barn to lay CAT6.  I was then going to place a 4 port POE switch (POE-4G1G) in the barn to connect those 4 cameras with the management port connected to the CAT6 that goes back to the NVR through the trench.  I'd put the switch in a small plastic box for protection but am concerned about heat.  This barn is not climate controlled and it gets quite hot here in TX.  We are having Verizon install their HomeFusion Internet service which I've tested and it works great for remote viewing once you get the Verizon router to pass the traffic from the WAN.  I'd connect the NVR to the Verzion router using the non POE LAN port.  I then need to connect the barn and only have POE ports on the NVR left.  Is that safe or will voltage be an issue?  I'm also concerned about bandwidth over the trenched CAT6 supporting 4 cameras.  I would then connect the two internal cabin cameras to NVR POE ports.  I need to be able to record by motion only on this system.  I haven't totally decided on the exact items I should use but placed the ones I'm considering in parenthesis above.  I'm very open for suggestions.  Thanks.