I have recently done Opua to Brisbane
twice. One a heavy slow double ender in Sept, hell trip , upwind all the way, slow, cold. The other in Dec in a 47 ft Catana
, absolute joy downwind , fast and pleasant, warm (ish).
will depend on the boat and time of year. Much prefer to wait a little, Tasman in winter sucks.
If it is a NZ registered boat you will need the full Cat 1 nonsense to be allowed to leave, if not it is up to the skipper
, some are pedantic about it, I am happy to skip a few of the items they insist on or a lesser alternative, but the decision to stay or go rests with the skipper
In short, need more info on the boat and the condition it and the gear