I don't know the laws in your area, but it would seem that raising the rent to market should be the first move. Shes on M2M, so I expect there is at least a 30 day period, probably 60, maybe a max percentage increase as well. So, along with the 90 day notice, add in a second notice of rent increasing at 30/60 days, or whatever. Unless you are in NYC, at which point, I wouldn't be in the landlord business. I do disagree on the heat being insufficient. It gets up to heat, but is a boiler system, so takes time. Instruct you tenant to LEAVE THE HEAT set at 68, assuming she has her own thermostat, this is how boilers work. Any radiant for that matter, takes time to heat up. It'll actually save you money, maybe give her a pamphlet. I also agree I would be planning on separate utils, and informing her of when the work would be happening (soon, early in the morning starts) and that you plan to install all new electric heating to address her concerns with the response of a boiler system, which she'll be paying the bill for (assuming she moves, don't actually do this, electric heat is only cost effective in parts of Canada near Hydro plants). You should expect to upgrade your windows and insulation to meet a minimum R value when transferring paying for heat to your (hopefully future) tenant, I expect your jurisdiction has a clause for this.