West Maui - cooking and eating on the cheap

I had a surprise invite along with a group to Napili Bay next week. We're going to try and keep our meals cheap by cooking at a questionably-stocked rental condo. What simple, few-ingredient recipes would you recommend for this kind of situation? I'd prefer to try cooking with whatever seafood is available in the area. Where should we shop?

Also, any recommendations for lunches and inexpensive dinners? Are there any food trucks, etc? I'd like to try as much Hawaiian food as I can because there's not much where I live.

Thanks so much, sorry I'm woefully unprepared.