G'Day Adam, and welcome to CF.
The trip that you are proposing is done frequently and if not in a hurry, can be a pleasant experience.
The first thing for a
novice to do is buy Alan Lucas's "Cruising the New South Wales Coast". Alan's
books are the best source of
advice for these areas IMO. He is a pretty conservative fellow and all the advice that he offers is from personal experience and measurements. He takes the soundings himself (with his faithful and delightful mate Patricia as crew) and has poked his nose into a huge number of places on the
East coast of Oz.
He gives advice on routing,
weather, facilities,
anchorages, moorings and all the other things of interest to a cruiser.
The bottom line is that if you have time to wait for good
weather, this can be done in day hops or perhaps one overnighter, and should not be too challenging. If you are on a schedule and must sail on some specific day, you can (and likely will) get your ass kicked!
In general, you will get more useful info if you ask more specific questions.
Finally, if you are in Brissie and want the
boat there, why are you specifically
buying in
Sydney? Lots of boats on the market in the Moreton Bay area...
Cheers and good luck in your purchase/travels.
Jim