The earliest house I know of was built around 1903 by architect Dickey at the corner of Pensacola and Lunalilo, owned by Edward Tenney, whom I believe was the President of Alexander and Baldwin. His wife planted the banyan tree that is still there on the grounds of the Barclay condo. His neighbor on the mauka side was Abigail Kawananakoa (aka "Princess") which is now the campus of Hawaiian Mission Academy. His neighbor on the Ewa side across Ernest St was a sea captain who had Tenney's little girl plant a tree (Wilhelmina Tenney tree) in his front yard.
What else do you want to know?