Expect the call to replace a lightbulb in the laundry area or a battery in the garage door opener. 

I told them I would bring them extra flashlights, batteries and water but they should get themselves perishables.  

Some have sealed batteries and some are replaceable.

Cheap curtains hung up on the first floor, a welcome mat, lights on a timer, battery operated fake candles on a timer, big size 11 men's shoes and big men's jacket hung by the front door, two empty dog bowls, a tie out in the back yard (for a dog), fan on a timer, foldable table and chairs with a tablecloth and centerpiece, and radio playing on a timer.  

I agree with the need of a furnace.Most mountain cabins have hot tubs.Emergency generators aren't cheap, but great to have during a sustained power outage.I've thought a battery backup system might be a good compromise.

Batteries go dead and you can;t get in.

Completion rates are even lower for solar (14%) and battery (11%) projects."

One thing we are doing now is we hired someone to do monthly walk throughs of our properties to make sure everything is in order (not just with the cleaners, but also the TV remotes having batteries, the pool table having chalk etc).

X has been homeless for decadesand stole battery packs from Lime scooters and electric bikes.While soddering (sic) them together in his unit, he started afire from the lithium battery packs.

I am installing wireless, ten year lithium battery combo smoke and carbon monoxide alarms in my rentals.