Separate metering costs

[Brenda Czich]

New investor needing advice...  I am interested in an older home that has Baseboard heaters, Hot Water, (Electric).  I was told that there was separate metering for electricity but then discovered there is a separate cost for heating that is born by the owner.  It's substantial, so I am left wondering why they did not separate the metering for this cost.  Is it because of an inability to do so, or the cost of it?  And if it is the cost, what is this expected to be?  It's a 3-story older home that has 3-units (basement, main and two upper-levels). 

Many thanks for any advice!