Changing Heat - Who pays?

[Mike McCarthy]

Just purchased a 3-unit multifamily with a single boiler heating system.  I'm changing over to mini-splits for both heat and A/C and I couldn't be more excited to put that cost with the tenants and give them control over their own heat AND offer A/C.  

New tenants won't be an issue, it'll be priced in and explained in their lease.

But I do have one tenant in a 2BR who has a lease through January, and she'll need heat this winter. Her current lease includes heat (and hot water which I plan on changing over too), so I can't just say "surprise, you're now paying for heat as part of your electric bill!"

I'm considering taking $100 off rent for Nov/Dec/Jan to compensate for the increased electric bills. And then renegotiate with a new lease.

I could instead add it temporarily to the 'common/landlord' panel, but that will probably require a panel upgrade, which is going to cost more than a few hundred $$.

Do you have any suggestions on how to handle it?  I want to do what's fair for both sides, but get these mini-splits installed before the heating season.