In the best of times, having a secure home or location is a necessity; like it or not, there are a lot of people who are just bad actors and it does not seem to matter where you live.
In a survival situation, that reality will be exacerbated; as normal, generally, law abiding people get desperate, they become more willing to do stuff that prior to the crisis, they otherwise would not have considered.
Add to that the bad guys, who will be just as desperate and the situation can become very dangerous and volatile very quickly.
That is why wherever you are during and immediately after the crisis, setting up a basic perimeter security system is critical.
The video on the next page covers how to set up a fundamental trip wire alarm system to ensure you're aware of anyone approaching your location.