sydney suburbs (Sydney)

Howdy,

We're looking to move to Sydney in July/ August from London and in need to find a good neighbourhood to buy a house in fairly soon after we relocate. We've had trouble finding an online guide aimed at commuters (similar to Protected content for London), but maybe some local knowledge might help - either with a good guide or with an actual suburb?

We're looking for a leafy suburb within reach of the beach, fast transport connections to the city centre (under 30 min station-to-station) and low crime (e.g. like Orpington or St Albans are for London).

Thank you,
A