Thanks for the responses. I ended up purchasing the Swann unit from Costco since their return policy is very good. If somebody recommends something better, I can return it as well. I will also tinker with it before installing the cameras to see what I am getting myself into. Does anyone have experience with this particular unit? How loud is the NVR? Would it be any louder than a typical 4 drive NAS, for instance?
Also, one installer I spoke with said IP cameras can bog down your network by using a lot of bandwidth. After I thought about it, it didn't make sense to me. The way I see it, it shouldn't affect my internal network because the cameras communicate directly with the NVR and the cameras should only affect my external network when streaming remotely (which any system would do), right? What am I missing? A lot of iPad and Xbox usage occurs at my home so I wouldn't want to interfere with my internet connection.