We charge our clients just $55 for each of the inspections and it includes all the necessary small parts (air filters, batteries, etc).

You can buy a 12 pack of 9 volt batteries on Amazon for $18.

Also, if you don't already have a separate power wire coming from the furnace you will need to run a wire, or use a battery-operated thermostat and now your get calls from your tenants because the battery is dead.

Invest in mining.. precious stones and natural resources for EV Batteries 

The biggest issues with Vivint is the maintenance of the batteries.

The lock itself will still work via batteries if there is a power outage or the wifi disconnects, you just wont have app features until power or wifi has been reconnected. 

I put this on the front and rear doors, so there is a "backup entry" in case a lock misbehaves (or battery fails).

Napoleon Hill, Dale Carnegie, Gitomer, Rich Dad/ Poor Dad, Cashflow Quadrant, Trump's "Think Big & Kick ***" and "Think Like a Billionaire"), I'm working on the Trump University's "Real Estate 101", and I've got "The Art of The Deal", "The Best Real Estate Advice I Ever Recieved, and Kiyosaki's "The Real Book of Real Estate", plus about a dozen more on their way from Amazon (Thanks to a bunch of loose change and the CoinStar machine offering no 8.9% fee by choosing an Amazon gift card rather than cash)I WAS going to check out one of the local AREIA meetings last night but clearly last night just wasn't the night for me (got out of work late, had directions on my blackberry and the battery died, then my car overheated in traffic...

Batteries last several years, but if you swap them out once a year you'll never go dead.

For example I always own two cars, thus a flat tire or dead battery (or even a motor blowing up) is an annoyance, not an emergency.