Hvac Rental How Much Does It Cost To Replace A Gas Furnace?

How much does it cost to replace a gas furnace? - hvac rental

I have a house, a duplex built in 1948 for rent. The gas furnace is inefficient. It's just a 770sqf for each unit and the gas bill is as high as $ 250 per month. It is a low-income neighborhood, I can not spend money to go the CVC? Is it worth repairing or is it better to buy a new gas stove? How much does it cost to buy the device and install them? Any other option than installing a new gas condensing boiler?