We offer renters heat for our private pool and and hot tub for $50 a day in the cold months, and that doesn't cover the entire cost of heating it. Even in early October when it was in the upper 70's in the daytime, it cost us $35 a day when we were there for fall break. Even if we crank the heater control up to 90 degrees, the pool still doesn't get warm enough for our tastes. The hot tub is another story -- it can be 32 degrees outside, and it'll heat up to 100 degrees in about 30 minutes.
I think the reason for the February rentals is that so many schools have a winter break in February. However, we have no February rentals, but it sounds like our house (4 bedrooms and 4.5 bathrooms) is bigger than you need, Whiskey River.