Mult-family with Single furnace and water heater

[Stephan Guna]

I recently visited a house marketed as a multi-family house going for a pretty good, price. I overall love the quality and everything with the house, it needs a bit of work, but nothing out of my range. All the houses I have visited so far all have 2 water heaters and 2 furnaces for each unit. However, this one only had 1 water heater and 1 furnace with the house. How would this work out? If I wanted to still rent out to both units, one unit is already occupied, but would that not lead to concerns of one person controlling the heat etc. I would prefer the tenets take care of heat/water, but I don't know even how this would be possible.