It works great batteries last about 10 months or so. 

I would still offer key so incase the batteries go dead or the lock gets stuck. 

It works great, but I need to change the 4 AA batteries every ~3 months.

Clearly I can't expect anyone to magically connect a neutral wire but I'm wondering if anyone has ideas past battery powered lights to give these guys some light.Of course... being from Africa living in a tent they live that way here too and cover the windows and walls entirely.

We are wanting to buy homes and multifamily charge rent and use that as income for ministry purposes and also to house missionaries and people in need for and from the church.

So, I invested in VictorPest Rat Zapper (Victor is the company that makes the original snap mouse traps) It runs on batteries and it zaps the rats with electric voltage, they die instantly.

Another nice tool was a battery operated metal skill saw.( I have a bosch 18v) 2 of the roofs had hips..

I also heard/saw a suggestion here that the owner chargers for cigarette butts they find on the ground.

This is cheap with battery-powered materials, if your local code allows it, significantly more expensive with hard-wired models if your local code doesn't allow them.

Replace all old detectors or at least put a fresh battery in.