I install them, but when folks move out I find that the smoke alarms are missing, batteries dead, etc. 

Those in support of tech, namely chip manufacture and battery tech., and energy.

Account Closed, sorry I didn't hear that, the batteries went dead dead in my hearing aids. 

In most cases it's the landlords, but there are items where the landlord and tenant may discuss and designate who wants to do it such as smoke alarm batteries, light bulbs, pest control, refrigerator water dispenser filters etc etc etc...Usually, if the landlord provided the appliance, the landlord is responsible for it's maintenance. 

Change the furnace filter, change the batteries in the smoke detectors (every 6 months, and keep a log for insurance to show you have done this) and inspect for any leaking faucets/toilets. 

In the eastern area of Cleveland - not the nicest but around university circle they have nice places. i invested closed to battery park, behind edgewater Beach but you have to be careful here you Walk 1-2 blocks and you go from like B to C-D pretty quick. let me know if you need further help.. 

For keypads locks you have basically 3 types, mechanical, battery, and internet capable.

It uses batteries, but I have never changed them yet.However, for this rental property, I am concerned about battery life, as I may not be around to replace it if one stops working and a guest comes. 

I would hate to have a fire and come to find out that she disabled the battery, and now people are asking you why didn’t you just move it.

Like the new Toyota Battery Plant, and UPS expansions.