GC isn't that far north really... If you want nice and warm you've gotta get above Brissy, like Sunshine Coast or Cairns. Theme parks are in GC though... But it's worth considering, if you want some heat.
We looked as buses for Sea World - there's a public bus I'm sure that goes somewhere near there. Maybe check that out??
Dream World and Movie World are a fair distance from GC, like over half an hour, so it makes sense that the transfer would be more expensive to there. You could prob hire a car for that one day for less??
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