We rent too and have changed it a fair bit ... it was only 1/2 insulated so we went out and bought some batts and finished the job off! That really helped keep the house warmer. Got the batts on special because the bags were ripped... only paid about $10 a bag for them. The owners paid $300 to have ducted system cleaned so we didn't mind paying for the batts... came in under $60. We also made thicker curtains than what was here.... but I know what you mean. Our owners are great though... give us great lea way to use the house as if it's our own. Let us use the fireplace... we dont' have to buy wood because there are so many huge trees here and our neighbours threw branches over into our yard too... love free heat... one night I cooked our entire meal in the fireplace! Foil wrapped spuds... damper... toast... and marshmallows for dessert! LOL would love a proper range though...