Question: what is the best tankless gas water heater to buy?
Answer: Rinnai RUC98iN Ultra Natural Gas Tankless Water Heater. ...  Rheem RTG-95XLN Low NOx Outdoor Tankless Natural Gas Water Heater. ...  Takagi T-KJr2-OS-NG Outdoor Natural Gas Tankless Water Heater. ...  Naiven NPE-240-A Tankless Gas Water Heater. ...  Noritz NRC661-DV-NG Tankless Hot Water Heater.