The second decision you'll need to make is whether to opt for a wireless alarm system or a traditional wired one.
62% of the people we spoke to have a wired alarm and 38% a wireless one.
57% of the people we spoke to own one of these types of alarms.
However, unlike a monitored, dialler or smart alarm, it won't automatically contact a named person or the police, so there is no guarantee that any action will be taken if you're out.
In all cases, you will need a central hub that connects to all other compatible devices via wi-fi, in the same way that a standard alarm connects to sensors around your home.
You can then connect elements to it, depending on the system you choose, including motion sensors, cameras, and lighting sockets that allow you to switch lights on and off when you're out.If not, do you have friends and relatives who live close by who you could count on to take action?You can install one of these alarms yourself, or you can pay a one-off fee to have it installed by a professional.It's worth thinking about the kind of area you live in before deciding to get a bells-only alarm.Is there an active neighbourhood watch that gives you confidence that someone will call the police in an emergency?You can install smart systems yourself, although a professional installer will know the best possible positions for the items you've chosen.Smart systems can be expensive, especially if you want to add a lot of extra components.This means you, or they, will be alerted when your alarm is triggered.These systems also allow you to control your smart security from your phone, even when you're away from home.We've tried out a number of smart home-security systems to see how easy they are to set up and use, and asked a security expert to assess how likely they are to deter an intruder.Visit our guide to smart home automation to find out what other smart security gadgets are available, including door locks and security lights.