Extinquish all pilot lights and shut the fireplace damper. Get probably a medium and a small Ozone generator. (what used car dealers and hotel managers and landlords use to de-odorize pets, tobacco, or other unpleasant smells, and remedy pest infestations)....Let them run, one in a return air vent, and one in the largest open area with all the doors inside the house open, and the cabinet doors, but exterior entrances, and windows locked and closed tight.... It will remove the oxygen in the house and thus.... all odors caused by bacteria, as well as suffocate all living bugs, mites, termites, mice, etc.. that are inside the house and make all the carpets and furniture smell like they were in a fresh spring shower, after the rain--probably about 4 or 5 hours in your case?............. Remove and donate all the furnishings, they will smell so clean and fresh.......Get some ODO-BAN, use diluted, as directed to wipe down and wash all surfaces as it is labeled. ... Decide if any walls need to be painted to be fresh looking. Caulk the holes from old picture nails, curtain rods, shades.... Use the same color thru the entire house or rooms to be painted, likely DOVER WHITE, by Benjamin Moore, would be a great choice for current painted surfaces. Steamclean the rugs if ODO BAN did not get them clean enough to suit you. Wash the windows inside and out. Clean the cabinet hardware as needed in all rooms...(no need to replace. IF they are discolored, spray paint them gold or what matches the other surfaces)Sweep the porches, and wipe down those surfaces, top to bottom, including in the garage. Use the oil removal product on the garage floor. Use the aerosol SoyBean based spray on all interior door hinges so they don't squeak, and on the door handles too if needed, interior, exterior, cabinet doors...Wash the light fixtures, and put in new style bulbs, a tone that is pleasing to the interior space if you have a choice...If the exterior is trimmed up and maintained, you are all set. There is nothing sadder than walking thru a fixed up house with grays, browns and purples or loud colors in every room. There is nothing sadder than having someone alter the appearance of a permanent asset in or out of the home for lots of dollars or in haste and than having to spend money to reimburse them AND than spend money to reverse their taste. A really clean home, even older styles, is much much better, to purchase for a price the new owner can than make into their own. I wish your family much luck and success in doing this for their parent's home.
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