How to split common area utilities

[Dion Watts]

Hi y'all

Recently purchased my first multi-family home last month with my sister and are looking for renters at this time.  I am trying to get some information from experienced landlords how they have split up utilities in common areas 

Our house is set up as a 2-story duplex w/ a basement for laundry/storage.  Thereare two electricity boxes (one for each unit), but the power for the common areas is set up in an interesting way.  For example, the front stairway is on power box 1 while the back stairway is on power box 2.  Also, utilities like the washer will be on power box 1 and the dryer is on power box 2. 

To me, can be a seen as a fair split between the two units for the power for the common areas, but I am not 100% sure all renters would agree.  Looking for any incites on this Utility split.  Good idea? Bad idea? Any ways to make it better?

Thank you