I am thinking on a trailer cam and just saa a wireless baby cam that you watch from the internet or your smart phone. Looked pretty neat for 99.00

Voice both directions and the camara veiwed up to 30'. Zoom and adjustable remotely. Any one triwed something like this?

I was wondering that myself. On another forum someone said they used a baby monitor so I need to do some more research.

I wired a camera on the back of my trailer to assist in backing it into my driveway when I want to park it.  It would be no big deal to put a 2nd or 3rd camera into the system and have some switches that turned on or off certain cameras.  I just inserted a plug connector that was located next to my regular 7pin Trailer plug. So I plug in two connections when I hook up the trailer, Standard trailer plug and the back up Camera .

You can buy back up cameras for $25 up to several $100 depending on the features and quality. With the cameras in place, some wired threaded underneath the truck and into the cab area, you just connect that to a display.  Most of the built in Nav systems have limitation on viewing a camera or DVD while the truck is moving forward. So you either need to defeat those safety parameters or install a second display that allows forward motion viewing. Mine automatically turns on when I put the truck in reverse. So I just have to choose to watch the default bumper reverse camera or switch over to the camera on the trailer.