Who needs a guard dog?
You do!
Rather than spend a lot of time writing this out, please just watch the video.
Worth the effort.
Here's how to buy them.
Single sensor and receiver.
Motion Sensor Dog Barking Alarm- Pir Wireless Human Body Detector Home Security 1Receiver and 1 Sender Alert System for Home or Office Auto Dialer Seldorauk (Pack of 1) a.co/d/5TIMi9K
Two sensors and one receiver
Dog Barking Alarm Motion Detector,Pir Wireless Human Body Walking Sensor Doorbell Door Security Alert System Device for Home or Office Burglar Deterrent (2Sensors + 1Receiver, White) a.co/d/gAsXiqe
Two receivers and one sensor.
Dog Barking Alarm Motion Detector,Pir Wireless Human Body Walking Sensor Doorbell Door Security Alert System Device for Home or Office Burglar Deterrent (1Sensor + 2Receivers, White) a.co/d/2jIcpBG
Enjoy!