It comes as no surprise that the more expensive high-end cameras tend to have more features than cheaper models. Of the higher-end cameras there are several features that set them above the rest.
Night Vision
Night vision comes at a high priority as crimes have a tendency to occur after dark.
Motion Detection
Motion detection is also desirable, but be sure that the sensitivity and range can be adjusted. This helps to stop windblown debris from being picked up by the alarm system unnecessarily. By properly tuning the system, you can also have a text message sent to your phone when motion is detected.
Saving Video and Images
The ability to save video and pictures externally is a useful feature to have, which comes in very helpful for law enforcement purposes. If a crime is caught on camera, the ability to play back video at high speed will help you find the event, and slow motion will help you determine exactly what happened.
External Recording
Higher-end models come with a separate DVR to record video. This helps if a great deal if your cameras running all the time.