I rent out the top level of my split-level house, and live in the basement with my wife and son. From a home security outlook, there are unique challenges living in the basement of a split-level house.
The primary challenge, of course, it that all of my windows are at ground-level. From the inside I can protect them with window sensors as a standard part of my ADT home security system, but that's only half the equation. The outside needs attention.
When you have windows at the ground level, you have to ensure that burglars won't want to mess with them. A great way to accomplish this is to plant rose bushes in front of them. This is exactly what we did, and honestly I feel like it has greatly improved our home security.
Our other concern, of course, is flooding. We actually have sandbags in our storage shed, but our primary protection is a flood sensor as part of our ADT home security equipment. We want the fastest notification possible in the event of rising water levels.
No matter where you live you can protect your home with a little common sense, a bit of work on your part, and having a monitored ADT home security and burglar alarm system professionally installed.