Video monitoring is now essential.
You need quite a few cameras to monitor an entire estate. In addition, you will also need floodlights with motion sensors to light up the area.
Only this will probably keep intruders away. A video system can be set so, it only records images when there's a motion in the image itself.
This saves space on the recording medium.

You can break in, but you can't get out
This is a custom made alarm system that's something for themselves.
This was Ordered by a friend of mine, who had problems with security in a assembly room, with some good technical stuff.
An alarm system supplied by the alarm companies do not catch the thief unfortunately.
This room had only one entrance and no windows. During an alarm sequence will the room be approachable hermetically tight....

This system can and will catch the intruder, if you wish to.
I'm so fortunate to have a friend who works in the "gas" industry. That is, he delivers anesthetic gas, to hospital, etc....
He have fantastic knowledge on this field, therefore much of this catch system is based on him.
In practical terms, the system is built over, motion sensors, magnetic relays, pressure sensors, magnetic valves, for black smoke and anesthetic gas, and solenoids'
for open and closurethe doors. In addition some timers and sound system for playback of messages.
The main system is based on 12 V DC battery power it's therefore not sensitive to power outages.
Alarm siren produces the same sound as the police use. It has a powerful volume of 118 dB, which means that many neighbors far away will hear it.
I think at the night, most of the folks on the housing estate will believe it's a police action.
A remote control turns on and off the system. The code is encrypted and randomly. Works well at distances up to 500 m, also from the inner side of the mainliving building.