Camera systems come in two flavors: Proprietary and Standard. The proprietary kind are the ones on sale at Wal-Mart and other stores. The good thing about them is that they allow inexpensive access to this technology. However, each brand of system can only be used with itself: it's not compatible with anything else. Standard systems, in contrast, are composed of standardized commercial grade parts, all designed to work together to provide infinite future compatibility. Of course, the Standard type are more expensive :( However, it's worth it since there are many more options available such as special types of cameras, pan-tilt-zoom lenses, special monitoring and recording equipment, etc. Price: Allot $500 minimum per camera for black and white, $600 for color, including installation. Housings can be several hundred also if they are for outdoor use. Most monitors run about $500 or less, multiplexers and switchers run from $250 to $3000 depending on size and type. Time Lapse recorders average $3000 including a supply of tapes and all setup, programming and user training. Request more info