Thank you, TropicalFlyer, for pointing me in the direction of the Shower Tree. ^ I'll have a rental car which will take care of both the luggage storage and transportation issues. Basically, I just wanted to make sure that I could hit the beach all day on our last day in paradise and still show up for the long trip back without smelling and feeling like saltwater.
And slippahs, thanks to you for you continued excellent insight on travel to Hawaii. Perhaps you could add the information about the Shower Tree to the sticky you mastermined in this forum.