However, in order to have at least some idea, you can use a special calculator on one of the sites of organizations professionally performing, commissioning and maintenance of alarm systems. The main determining factor in calculation is the total area of the room. For example, the owner of an apartment of 75 «squares» will pay about 38-40 thousand rubles for installing an targeted (radio channel) alarm. The payment for its service will be about 3,800 rubles per month.