You can split electricity starting with the next lease renewal for each apartment if you install separate meters and panels. A few cities will allow you to split electricity if you kept the existing meter but added submeters and subpanels for each apartment.
Similarly, splitting the heat normally requires separate furnaces. In a few cities you can install timers and meters on forced hot water furnaces to split the cost of the heat in proportion to the readings on the respective timers and meters.
It would be okay to install a furnace of a different kind for example if two units shared a forced hot air furnace, you could install forced hot water heat in one unit and keep the existing furnace for the other. For this to succeed you would need to be able to lower the blower speed for the forced air furnace now outputting to fewer ducts.
In one condominium complex where I owned a unit we could put meters on the FHW heat but residents complained and nitpicked about upstairs apartments being inherently warmer and the meter conversion was nixed.
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.