Hi Dave,

I attempted to email you directly but got a bounce.  I got open water
certified on Kauai and wanted to provide you with info that you may
find useful.  If you can please send me a note to
squelch@<REMOVE>pacbell.net I'll forward you the info.

-Mike

Assuming that you mean you'll do your class and pool work in California or
have already done so, and then get a referral for the Open Water dives in
Kona, just bring the same stuff to Hawaii that you're buying for your course
(i.e., mask, boots, fins, snorkel).  I've never been on a dive boat in
Hawaii where there wasn't someone renting gear.  Hawaii is a very popular
place for tourists to get in just one day of diving during their trips since
(a) the diving is very expensive and isn't all that great, (b) there are so
many other touristy things to see/do while in Hawaii, and (c) most people
don't get to Hawaii very often because it's expensive and far away.  The
rental gear I've seen on the dive boats always looked fine and I've never
seen anyone having problems with it.  On the other hand, my cousin rented a
wetsuit with a broken zipper and a leaky reg from Maui Dive Shop a few years
back.  A lot of the shop rental gear on Maui is beaten up on shore dives, so
that's a different story from the boat rentals in Kauai.

I've only dove with Bubbles Below there.  They were certainly competent
enough to do open water referral dives.  November is the off-season, but the
dive operations on Kauai are all pretty small and you need to make sure that
an instructor is available, so it is a good idea to make reservations.
Water temp will be 77-78, viz is always low on Kauai because of the runoff
and algae and you'll be coming during the winter stormy season so there's
always a small chance you'll be blown out of doing your open water dives
altogether.

Just as long as you know you're tossing two days of your vacation.

Can't help you with the shop.  I'd suggest just buying the usual
stuff, mask, fins, etc.  Either rent in Kauai or, if you plan on doing
some real diving, consider renting what you've learned in at home.
You'll be (hopefully) familiar with the gear, and that can help a lot.

Depends on the shop.  Pick one and call them.

As far as the water is concerned, remember that the water temp in
Hawai'i is kind of cool.  During the winter months, the north side of
the islands are pretty choppy, so make sure you're diving on the lee
side of the island.  Most shops are smart enough to do that, nothing
like having a boat load of divers tossing their cookies.