How can I find the best vacation home in Hawaii?

Contact a local realtor (and bring a lot of money).

just go check them out

You start by defining what’s “best” for your needs and desires, and as you search for vacation homes which best match those parameters you define which desires you can compromise on. 

If your list of needs is true and accurate then there can be no compromise on those. Any that you can compromise upon were clearly just desires to begin with which were miscategorised.

But as it’s just a temporary vacation home you leave yourself more wiggle room on those parameters than if it was a permanent home.