Aloha!
I am a DN stationed in Honolulu, Hawai’i, and I recommend the Kuhio Banyan Club for those wishing to stay longer. It is centrally located in Waikiki, on Kuhio Ave.
I also recommend buying the week pass for the Trolley Hawai’i because it has four lines, and although it works as a hop-on/hop-off tourist thing, it is very useful to get to the main places within the Central/ South Shores of O’ahu. Also, as they hire local drivers ( natives), you help the local community. Tip: Take the Blue Line, get out at Sea Life Park, and walk to Makapu’u Beach. It is a beach frequented by locals, so you will be off the beaten track. Return to Waikiki with The Bus ( local city bus).
Groceries: choose the ABC Store. They are everywhere on the island!!
Aloha Mai!