When i arrived she handed me a bill for $200 for batteries that had been replaced in the chair. 

You have no idea what is under there or how they treated the top cap.Who would want to have a garden on top of lead and old batteries?

Regardless, batteries and back covers seem to go missing constantly whatever the remote brand. 

Right, the list of things to maintain and/or replace is never ending; rugs, AC filters, light bulbs, water filter in fridge, detector batteries, pest control, coffee maker, stove eyes and pans, silverware, bowls, glasses, sofa cushions, pillows, blinds, brooms, mops, vacuum, brushes, shower curtains, bath mats, beach towels. 

Tenant maintenance includes changing the HVAC system filters, batteries, trash cans, electric light bulbs, fuses, resetting circuit breakers, cleaning of appliances, as well as window air conditioning units, humidifiers, and de-humidifiers, or any other services not specifically listed as supplied in this Lease Agreement at Tenant’s expense.

The batteries last about 6 months in each camera before recharging (aka no wiring either). 

You might find the property you buy is landlocked and your first job as the new owner is getting legal access.As for access to the interior of the house, if you have a battery powered drill you can get access. 

@Zachary DealIn the Tahoe Reno, NV market we are seeing more interest in MTR because of the influx of tech and manufacturing jobs with Tesla building the Semi-truck factory, Panasonic building batteries, and Redwood Battery recycling the batteries.

Batteries in those units last much longer than WiFi due to the wattage of the radio.

If you are in a heavy sun, high cost of electricity and high rate of usage market, and you buy the panels, and you can resell to the provider rather than maintain your own batteries, you probably will make money especially if you hold long enough.