Study up on frequencies. I don't know enough to advise. Maybe it's not an issue with the newer ones, but I remember hearing unfamiliar voices, and it turned out our new neighbors had the same monitor. I was hearing everything they said in their home. Needless to say, I figured it probably could go both ways, and stopped using mine.

Some newer baby monitors encrypt the signal so that no one can eavesdrop on it. Look for terms like FHSS, DSSS, DECT, or just plain "encrypted" in the product description. Also, if you have a 2.4GHz Wi-Fi network, the most common type, using a baby monitor on the same frequency may slow down your data rate, and likewise the network could cause a bit of interference on the baby monitor, though usually not very much because the actual frequencies in use by both at any instant change over a hundred times a second.

This was the one we got at my shower. I originally didn't want a video monitor, but I am glad that the ladies in our camping club decided to get together and buy it. One of my favorite things, two years later still works great! http://www.summerinfant.com/Products/Monitoring/Video-Monitors/Complete-Coverage™-Color-Video-Monitor-Set.aspx

I would go with ant that are made by Greco. Look for the 2 way and vibrate functions, they are as useful as getting a text message if your child is loud enough for the sensors to pick up on it!

been using a samsung model for 2 months now, really happy with it. been using it as a indoor security monitor and works anywhere you can plug it in.
http://www.amazon.com/Samsung-SEW-3036WN-Wireless-Monitor-Infrared/dp/B009M8P2CW

also available at target same price. good night vision outdoors ~ 10 feet. sound is a bit on the low end. try it out.