Wanted to add a health tip for all you investors! Adding an ozone system to the duct system eliminates mold from ever being an issue. and increases the health of the occupants. Source of info..."Flood Your Body with Oxygen" therapy for our polluted world. by Ed McCabe. Ed spent time in a New York jail for supposed tax evasion, but really for espousing oxygen use for health, before writing this book. He knows the truth and shares it in this book.His advice has saved lives by the thousands, including my husband's.