Plan your cameras before you buy them.

Most homes start with three to five cameras covering the front door, driveway or garage, side access and the back yard. Small businesses often add a counter view and a rear door. Start from the entry points and what you most want to see, then add coverage. See how many security cameras do I need.

Higher resolution gives more detail when you zoom in, but it also uses more storage and bandwidth. The lens and where you place the camera matter as much as the pixel count. Choose resolution for the job each camera has, such as recognising a face at a door versus watching a wide yard. See camera resolution and lens choice.

It depends on how quickly you would notice a problem and any obligations you have. Many homes keep a few weeks, and some businesses keep longer. Storage is sized around the number of cameras, recording quality and the days you want to retain. See how much storage does CCTV need.

No. A recorder records to its own hard drive without internet. You need a connection only for remote viewing and phone notifications. If the connection is slow, live viewing may be limited, but recording continues. See viewing cameras remotely safely.

On compatible systems, human detection is designed to identify people rather than simply detecting movement, which can reduce alerts from animals, trees and rain. It is not perfect, and results depend on the selected camera, the recorder and the lighting. AI features vary between models. See Dahua AI detection features explained.

Surveillance law differs by state and territory. In general, audio is treated more strictly than video, signage and notifying staff matter, and cameras should not look into toilets, change rooms or a neighbour's private areas. This is general information, not legal advice, so check your own state's rules. See signage, privacy and neighbours.