I assume you are running composite video with no Pan, Tilt, or Zoom functions? If the customer wants to upgrade to a multifunction camera housing that moves and does other tricks, using a coax works well. Otherwise you will have to pull another cable to run the control signals. I do not believe that the over the coax control systems work well with baluns.
One other thing to look out for when using coax, when grounding the shield at the camera, if the local ground is at a slightly different voltage than the ground at the monitor / DVR, hum bars may show up.
LarryC
