1. Inflation 2. cost of new land release and compliance 3. council contributions 4. population concentration (ie HIGH urbanisation) 5. high immigration NET - huge 6. Biggest square metre new residences in OECD average - FACT - 215 sqm (vs say NZ at 196sqm - 3rd highest) 7. higher commodity prices (ie copper in homes) 8. massive spending on home improvements - estimated at 1% + of nationwide valuations per year and INCREASING)
and BG asks "so why do people think its now worth double"
well, it depends on location, cost of new land and building, and scarity of land near the most common workplaces.
economics 101 really
and the other emotive things
1. family security 2. potential to improve 3. untangible personal attributes, like location and convenience (undefineable by "expert" individuals) 4. character.