Have you tried Friends of the Sun in Brattleboro, VT? If they don’t do it, they’ll probably know someone who does.

Edit: something else I thought of…unless the homeowner did it themselves, the furnace was probably installed by the manufacturer or a service tech. A lot of these places leave stickers or tags identifying who did the work. You can try calling the manufacturer and find out from them who installs/services their stuff in the area.