Firstly, real estate listings are notoriously inaccurate, even in the slim chance they're based on the county records, which aren't exactly paragons of accuracy either.
Secondly, there are all sorts of different gas appliances besides the HVAC system. Water heaters, dryers, ranges, gas fireplaces, pool heaters, outdoor bbq - any or all of them could run on a natural gas feed and still have a heat pump.
Came here to say the same.
Firstly, real estate listings are notoriously inaccurate, even in the slim chance they're based on the county records, which aren't exactly paragons of accuracy either.
Secondly, there are all sorts of different gas appliances besides the HVAC system. Water heaters, dryers, ranges, gas fireplaces, pool heaters, outdoor bbq - any or all of them could run on a natural gas feed and still have a heat pump.