We came in on the cruise ship and by this time I just wanted to be away from all the people. We rented a car in Kona, found a place to eat (Big Island Grill yum!!! Try the Loco Moco w/ Spam) and then got as far away as we could.
We stopped by Kona Boys headed South, rented snorkel gear and they steered us to a grocery store for drinks/snacks and to Ho'okena Beach to get a little bit of R&R. Do this! Bathroom access & beach chair rental. Seeing dolphins and turtles isn't unheard of. Careful with the dark sand though...it gets super hot. Note also, Huli (streetside) BBQ across the street from Kona Boys was delicious!