I've heard Costco is the place to go but I still anticipate it will be more expensive then at home. 10 days, three adults and three kids. Plan for probably two meals per day at home. Won't make really elaborate meals but we are on vacation so will be cooking. We currently live in Florida where groceries are medium priced for the US. I would estimate that to be maybe $250 at home. Any guess on a Hawaii grocery budget?