The problem with those free installation rackets is the fact that they typically only give you one door sensor and 2-3 window sensors. If you live in a teepee, you'd be covered, but if you live in a house, you're screwed. They really rack up the cost of installation by adding on extra doors and windows - which is necessary just to a get decent basic system that'll cover your ground floor. (I sold home security systems for Protection One for two weeks.
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