Having installed hundreds of CCTV systems for clients ranging from simple webcam/pc setups to high-end 32 camera night vision & thermal imaging solutions the main things you need to keep in mind are:
- You get what you pay for! Sounds obvious but you'd be surprised how many people penny-pinch and then complain when they really need a clear image for identification purposes and all they end up with is a grey bunch of blobs.
- Your system will only ever be as good as the cables you are running it on (unless it's wireless but best to steer clear of wireless for anything more than a simple 1 or 2 camera home install). If possible pay a professional to do your cabling especially crimping/soldering the connectors in place. You can save a bit of money by running the bulk of it yourself.
- For high-risk installations, have the collected image data streaming off-site as well as being stored locally. The first thing a professional (or even an amateur) intruder will do is locate the DVR and steal or destroy it thus rendering the whole setup useless.
- If night-vision is required only use CCD cameras as CMOS cameras are ineffective in low light conditions. When it comes to infrared lighting, you are much better off with several smaller light sources working in a flood-light type arrangement as opposed to a single high powered light source.
- For a home installation, never have more than one camera visible from the outside otherwise it can attract possible intruders wondering what you have inside that is so important to warrant several cameras.
- Infrared light barrier/beams connected as a trigger for recording are a good idea to save on the high amount of false positives generated by motion detection.
If you need anymore advice feel free to ask.