Instead, mix a solution 50/50 alcohol & water or vinegar and water.I'm in Calif and the house has a Western exposure w/o shade, so to reduce the heat load, we added a tint to the outer pane which reduces the light transmitted into the room.

Note I'm not contemplating repairs / maintenance type stuff, such as sewer mains or 1) Moving a home to a new location (as in so expensive you're nuts to contemplate it)2) Replacing / significantly changing external look / structural elements / adding a story3) Replacing vinyl siding with full brick or stone all the way around4) Replacing old heating (baseboard radiant) with new, such as a heat pump and forced air5) Updating Kitchens6) Updating bathrooms7) Replacing floors (like carpet to hardwood or stone)8) Updating fixtures9) Painting

With insured loans, the issue is when a section of the house, usually a converted attic, lacks a "permanent heat source".

The chimney is either letting cold drop into the house,,,or shipping heat outside by the natural rise of heat.Furnaces /boilers with pvc venting dont. 

The unit has been unoccupied for 2 years and the AC/heat was completely turned off. 

If a pipe froze in your unit, and you do not use heat, you are going to be liable.

These "park models" that I have an "in" on are 12' x 40' and have central a/c and heat with 2x4 walls, shingle roofs, and vinyl siding.  

I have 2 years experience as a Regional Manager for a Heating and Cooling company. 3 years of welding experience and certifications, Electrical experience, and concrete management experience.

I did this many years ago on a heating job and save many thousands of dollars. 

Most don't know enough to ask about sq. footage (but they can tell when they walk thru the property).Big items like garages, included washer/dryer, central air/heat will command more money.