If you have an existing written lease with a term remaining on it, you are under no obligation to change what you have already agreed to with your landlord. Most rented and approved rentals have their own separate utility meters which go with the unit rented.Your landlord cannot force you to pay utilities for some unit you are not using and which you never agreed to pay for. If the landlord insists that you pay the utilities for the two units, you should insist that you have use of the two units in exchange for paying for the utilities for the second and third floors. If he agrees, you can sublet out the third floor possibly and lower your overall rent.Good luck.