Batteries, forget about it. $10K.Still, it may not work for everyone, but it's an interesting option. 

Depends on what you are doing with the house, if you are gutting the place and putting new wiring in, then you may have to have hardwired smoke detectors put in to meet current codes, if you are just painting the place then you can get away with battery operated smokes. you will need utilities hooked up and either working or up to code, depending on what you are doing.

If there is no work order for sometime and then scheduling a walk through would be fine, or even telling them you are coming in to change smoke batteries.

The usual and customary battery of insurance coverage.For those of an age that are looking at LLC membership as a means to avoid Medicaid look-back issues....here's an informative article.  

You can install a backup pump that runs in a car battery for power failures if they're common in that neighborhood.

Have a backup system that runs off a 12 volt battery?

The leases do not specify landlord has to handle fire exit batteries, bulbs, etc.

Battery drills, sawzall, dremel, circular saw, bandsaw, Maxi-rooter sewer machine, pistol snake, propress, threader, feed through socket sets, open end gear wrenches, transfer pumps, etc.  

When the batteries in them die, which they frequently will on the exterior entry doors, and your tenant(s) gets locked out, they're SOL until the PM gets there to change the batteries.

Adam Leitman Bailey’s eponymous firm inked a deal to sublease 26,000 square feet from the law firm Hughes Hubbard & Reed at One Battery Park Plaza near the tip of Lower Manhattan, sources told The Real Deal.