In our summer home, we have a professionally installed, UL-listed monitored system that includes, among other things, exterior intrusion, glass breakage, motion detectors, cold temp sensors, and water leak sensors in the basement. Also integrated smoke and carbon monoxide. Both copper wire and wireless monitoring. Main house and guest house. We pay about $1,000 a year for monitoring. Worth it, partly because we are not here seven months of the year, but overkill for some. Lots of valuable stuff inside.
Our winter home has a system that is not connected. However, the place is a fortress, with 24-hour guards, keyless entry system, and 33 cameras on the property that record HD video. Central fire monitoring system and sprinklered throughout. No need for a separate alarm.