I am definitely just an observer here and not really able to help you. But as such:
Kudos to you!
& All the Best.
& Keep us "dreeming non (yet) dream fulfillers" posted.
Some random thoughts - not sure any one of them is helpful:... hopefully...:
Shore diving at a benign location, with no or very little current (say 1/2 mile per hour or less) and reasonably easy entry and exit and little tide activity (or planned and executed cortectly around slack tide) is a bit more work in prep and getting there and getting in and out than a boat dive, and should be a whole lot cheaper. But you do want to be darn sure to not end up on a current to somewhere thousands miles away... And that part is more local knowledge and "knowing sea stuff" (can be done w/o being a seaman) than what an actual PADI class or such would teach you - imho.
You are in CA? At or near the coast?
Why not hook up with people through an LDS or meetup for the purpose of getting a few shore dives in locally?
Stretching the budget = sensibly minimizing dependencies ... meaning:
e.g. buying and maintaining a compressor instead of getting airfills likely is the wrong way to go (maybe more convenient than cost effective, getting a yearly air card at an LDS may be better...
but e.g. working towards becoming a competent diver and competent on sea states, currents weather etc. ... and eventually a competent solo diver. I would judge that as helpful in many ways, including scouting, planning and executing safe budget shore (or kayak) dives that finding budfies for may or may not be easy.
Practice navigation (UW) to the point where you can trust yourself and have a good idea how much you need to expect to be off and how to plan for, deal with that.
Sounds like you must weigh (location wise);
"local low cost dive opportunities (shore dives)" vs. cost of living vs. income opportunitoes.
If those are the main considerations, are you sure the islands would win out over coastal CA (with one of the better job markets around)? (I am asking, I wonder, I do not know - are you thinking of it in that way or are the islands calling - period?)
Was on Hawai only once (about 20 years ago). Snorkelled a lot then (no scuba). Big Island and Kauai. So I cannot speak for the diving... but shore entries sure are to be found... And we spent 3 days on the big island in a luxury hotel, which at the time, even at 50% off was a big splurge for us, so we made up for it by staying 4 days on a then free campground. Which we did seem to share homeless. It was a great help to afford the vacation, but all our belongings staid in the car, with us... nothing stayed on the campground while we were gone out and about. I certainly would not have left valuable gear unsupervised.... The campground to us was not a place to stay just a place to crash for thr night. I woukd look at that sort of thing as well as staying on the beach etc... only as a temporary solution while scouting things out. You obviously need a real place to live... that also allows you to hold down a job ... and maybe if you like it grow roots...
Those Islands are a long and costly way out. Travelling to and from costs... If on a budget you sort want yo be fairly sure this is were you want to be ... all or the most of time...
If so, I very much root for you...