Here's an idea for you -- property evaluation. It's not hyper-specific to your monitoring system, but it would be very interesting to understand before buying a house:

1. How loud the neighbhorhood is over time periods, eg sat night vs tues morning 2. air quality, enviromental factors, etc. 3. What percentage of vehicles/people/devices are net-new (over a time period) versus recoccuring, as identified by MAC.

I would personally pay in the low hundreds to understand overall loudness levels for a house I am about to buy, although I am fairly sensitive to sound. My wife would probably pay for the new-new people metrics.

IMO, you could charge a per-device report and deploy a unit for a week, much like a home inspector report. It would give you a revenue stream on the buy or sell side, and let you own your devices as you iterate on the sensor package.

Anyways, just my 2c, gl with your PoC.