The fact that most people aren’t aware of is that the highest average household income area on the Big Island is in City of Hilo, not in Kona or Kohala on the west side of the island.
You can check it on the USPS website here, it shows median income by the routes. The top route in Hilo (zip code 96720), the median income is $89.41k, the top route of Kona (zip code 96740) is $79.84k.
The Hualalai Resort, whcih is considered to be the most expensive neighborhood on the Big Island, is mostly owned by out of state peple rather than residents.
There are many medical facilities, universities and government officies as well as the offices of Mauna Kea observatories in Hilo, and many doctors, pharmacists, professors, attorneys and scientists live those area with high household income in Hilo.
These area are mostly owner occupied and rarely are there homes available for sale. When any do come up on the market, the peoperty is usally sold quite quickly.
The west side of the island where there are a lot of resorts, many peope acquire properties as a second home or for an investment, and there are many homes available for sale.