Water meter-water company.  

What if you turn on water and it goes everywhere.

Water overflowing the sink, seems more plausible than some missing caulk.  

And I will state different jurisdictions have different rules, processes, expectations, etc.In my area you are required to have a permit to swap a water heater.

City water with one main at the street and how will they bill. 

The meters are read electronically with 3g and you get great reporting in their water scope platform.

I used to live in the city and the taxes and water bills are nightmares.

Don't forget to change all your faucet aerators and shower heads to low flow it makes a huge difference as well as far as water usage and saving HOT water. 

If the water bill is $100 a month, increase the price by 20% (or whatever you decide is fair) to compensate you for the time required to split and bill and to cover additional use when tenants squander the utility.

I would also look at the availability of public water and public sewer, if not at the site how far away are those services.