Ting Fire Detection Sensor, just plug it in and connect to the Ting App. Monitoring is just 49/year.
We used this in a former home for 2 years. Sells new for 99.

From Whisker Labs:
Ting is the only solution that helps protect your family and home from the devastating impact of electrical fires through 24/7 detection and mitigation of hazards before they become serious threats.
Sophisticated, Yet Simple Sensor:
Just two minutes to install
A single sensor monitors your in-home wiring, plugged-in devices, and incoming power
Real-Time Alerts via the Ting Sensor App: Immediate hazard alerts
Power outage notifications & more
World-Class Service for Ting-Identified Hazards:
Ting Fire Safety Team guides hazard mitigation
1,000 labor repair credit
30-day money-back guarantee
Ting is statistically proven to prevent ~80% of electrical fires, significantly reducing electrical fire risk in homes. However, Ting alone cannot eliminate 100% of electrical fire risks.

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