People change housing needs as they go through different phases of their life. Newly independents with low income would probably go for rentals. As they earn more or become married, they would be buying their starter home or an apartment in Brisbane. As children start coming, they would upgrade to single family homes near schools with more rooms, large backyard, and a fence.
Once the children moved out and become independent, empty nesters would be looking into the many empty rooms and considering downsizing. The school crowd would suddenly be too rowdy, and the commute too tiring. Burst pipes, fences to mend, yard to maintain, and roof to clean. The house would just become too much to handle.