Smart home security: where to actually start
The order to add devices in so each one adds real protection instead of another app on your phone.
Most smart home security disappointments come from buying in the wrong order.
Start with connectivity. Every camera, sensor and alarm depends on the network. If your Wi-Fi does not reach the garage reliably, the camera in the garage will not be reliable either. Fix coverage first.
Second, add detection at entry points. Door and window sensors are inexpensive, use almost no power, and tell you something happened before anything is on camera.
Third, add cameras where you need to see what happened, not everywhere. Two well-placed cameras with good light beat six pointed at dark driveways.
Fourth, connect it to a response. A notification nobody acts on is not security. Decide in advance what happens when an alert fires: who gets it, what they check, and who they call.
Only after that does automation — lights on movement, scenes, schedules — add much. It makes the system pleasant to live with, but it is not the protection.