Cold air returns in basements might also want resizing for more moderen furnaces; changes can broaden quotes but restrict blower
https://www.scribd.com/document/982154415/Assessing-the-Cost-of-Furnace-Installation-DIY-vs-Professional-Help-127396
Cold air returns in basements may need resizing for newer furnaces; variations can building up expenses yet preclude blower stress and noise.