From: William Blake
very tricky question - and I note no one has been quick to jump in.
however ... here goes.
The trend over the past 10 or so years has been back to the city. The dream of the 60's and 70's for a big block in suburbia is gone.
This has seen significant demand for property within close proximity to the city. These areas have boomed.
The other aspect for growth in these areas is close proximity to other amenities such as beach, cafes, schools, theatre - those suburbs considered trendy or fashionable have had significant growth in comparison to their neighbors
eg. Balmain (Sydney), West End (Brisy), Williamstown (Melb.)
In contrast suburbs which are considered troubled and without a certain ambience (eg. Footscray in Melb.) despite being closer to the city have not grown as rapidly
In essence it's a supply and demand thing - my tip is to look at suburbs that have boomed and buy in their cheaper neighbor - it wasn't so long ago that both Balmain and Williamstown were working class ordinary suburbs - demand for city property is not going to disappear