Help on Sydney suburbs

We seemed to have most things planned then the job my OH would be getting may mean he wont be working in Brisbane but Sydney.

So now I need peoples help please I have a 7 year old boy and we would be looking for areas near to schools but close enough for me to get into the City by public transport.

We are looking at a 4/5 bedroom 1 storey house as I am disabled and cannot cope with the stairs in a nice area where he can go out and play, something he does not have the chance to do here.

Help with areas to avoid would also be much appreciated

pm if you wish

Cheers