In an area that has a long, proven history of strong capital growth is one that is likely to continue to outperform the averages, and this is largely because of the demographics in the area.
These suburbs tend to be those where a large number of owner occupiers desire to live in the area, because of lifestyle choices of offer.
I look for suburbs where wages (and therefore disposable income) is increasing above average. This translates to being an area where locals are able to and prepared to pay a premium price to live there, putting a financial floor under your investment property.