Thank you very much for your reply. Your advice is appreciated. After reading other threads, I now realize that there are far more "flavors" of systems than I thought. I think my next step is to find out exactly what kind of cameras are on the house. As far as a DVR goes, in addition to being absolutely sure the new DVR will be compatible with the existing cameras, I'll be looking for simplicity of the included software. That Q-See software seemed very complex to someone like me. Again, thank you!