My friend and I will be in Honolulu for 5 nights then at the end of our trip we booked a trip to Kauia for 2 nights. We arrive back in Honolulu at 4:30pm. Our flight back to Chicago is not till 9pm. We were thinking of storign our luggage and then taking a taxi to do some shopping, sightseeing. IS there a storage at the airport? We are concerned we may not beable to cehck in our luggage early,. We are flying United.