You could realistically target snapper, kahawai, trevally with softbaits and small lures casting off the rocks, up north. Down south, likely just kahawai except for a few spots in the sounds. I've caught all sorts off the beach/rocks - gurnard, etc - but that's the likely 3.
A kingi off the rocks is a possibility but you'd really want a gruntier setup than you'd use for the above to target them with a higher likelihood of success.
What's your budget like?
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