Answering a question like this is like trying to answer ‘how long is a piece of string?’ The truth is that there is no right or wrong answer. The amount that you should spend on a security system really depends on your need and your budget.
Getting a cheap security system if you have valuable items could perhaps prove to not be cost effective, and at the same time, getting a really high tech, state of the art, all singing and dancing expensive security system when you have very little of value seems pointless.
Speak to your security camera installers and ask their advice. You need to come up with the right system that fits inside your budget. However, you must be prepared that if your budget is low but your need is for something a little more expensive, then it might be worth increasing your budget so that you can get the system that meets your need – if you want to protect valuables then you will need to compromise.
You also don’t want to be scrimping on camera quality. If you choose a cheap, poor quality camera then any images they capture will be hard to see, which defeats the object of having the camera installed in the first place. You could compromise on this by getting fewer cameras, but ensure that the cameras you get will cover the main entrances to the home at the very least.
Installing a security system does not have to be expensive, it can be planned to suit both your budget and your requirements – speak to your security camera installers, they are the experts after all!