I don't think that security systems generally come with a home. You can ask the realtor though. There's a chance that the equipment has been left behind. In that case, I don't think it would be active, and you would have to hire a company to come out and have the system activated. Different companies could have different ways of doing this, but you'll never know until you ask around and do your research. I hope you're able to figure this out and that you're able to keep your house safe with a security system.