Getting estimates for a new furnace in a fixer upper I just bought. Local guy installs Rheem. Any good? How much should a 75K BTU High Efficency Rheem cost. Not installation, just the price of the furnace. He is telling me he is giving me a great price at $1475 for the furnace and $1785 for all new duct work and $400 labor for a total of $3660.