Good advice, wing foiling is pretty much the same advice as wavesailing.
I would suggest that you choose between locating yourself at either:
Long Reef* see the places up the peninsular (the northern beaches)
OR
Cronulla and Botany Bay area for the best flatwater. This also gives you the choice of going south for a short trips to the Wollongong area or (an hour and a half by car) to Gerroa.
This place is a freak of meteorology. Seven Mile Beach is officially known as the windiest place on the entire east coast when a NE kicks in, it is as reliable sailing spot as any.
* Long Reef
will be more expensive than Cronulla, this may be a nightlife choice.