I have a 4 unit building with one water meter, so I will be responsible for paying for the water for the tenants. I know water fees are different depending on the municipality, but I wanted to get an idea from people who own multi-families. What is your typical charge for water on a 4 unit building? 

I can't tell you the charge as we are on a well but I can tell you that with six units we run at about 34 gallons a person per day.   I do that calculation every time I am at the property and we have gone from 77 to 34 and holding at that number with a little variance.  We have no washers which will impact your costs. We also have 3 of 6 low flow toilets. 

Get the history on the property, and find out how old the fixtures are that will dictate some of your volume.  Try to do early leak identification, the majority of the drop in usage was the low flow toilets and the leak elimination.  Hope that helps.  

My 3-unit (fully occupied: 2 bed, 2 bed, 1 bed) averages approximately 10,000 cubic feet per year at $27.98 per thousand cubic feet (plus a meter charge of $50/year).

In all, I pay approximately $300 per year in Water and another $300 per year in Sewer, which is just estimated off of water usage. Grand total of $600/year for Water+Sewer combined.

Check out your city's Water & Sewer Department website for billing information.