Batteries should last a while in warm weather.

Given AirBnB is all rating and reviews, I do not want the risk of someones phone being dead, the internet being down, or batteries being dead, etc.  

There is also VinFast, WolfSpeed, the Toyota Battery Plant, ... large pharmaceutical companies, manufacturers, energy producers, and a diverse cross section of other industries who are moving to or expanding within an hour of Raleigh.

TASK Confirm all dwellings equipped with the proper security devices Replace all batteries in smoke and carbon dioxide detectors once a year.

The only caution that I would give you is to modulate your mailers. 

I had to bring my car battery home with me at night lest it be stolen.  

I would recommend bringing some extra batteries in case one of the smoke detectors dies before he shows up. 

A concern would be that the batteries would be dead forcing my tenants to be locked out. 

Other than that, soap, some batteries AA & AAA & 9v, notepad pen dishwasher tabs a smelly candle dog treats poop bags TP paper towel a colouring book/ crayons if they have a kid some Lysol wipes and such. $20 gift certificate for pizza joint hand written “moving sucks, this may help”.

Get the smoke detectors with 10 year batteries, put one in every bedroom, every hallway, and everywhere but the kitchen.