Rent and good areas to live

if all goes well im starting a new job in the north sydney area in December.
im originally from Newcastle and had lived in mosman for a year but other than that i dont know much about sydney
which areas should i look at moving too?
are there any real shit areas that should be avoided?
any areas that are over the top in terms of rent?
and commuting times to North Sydney from these areas?
im originally from Newcastle and had lived in mosman for a year but other than that i dont know much about sydney
which areas should i look at moving too?
are there any real shit areas that should be avoided?
any areas that are over the top in terms of rent?
and commuting times to North Sydney from these areas?