I was reading about the upgrade to URA Space which now reports 5 years' worth of private property transactions. Five year transaction history is really far more informative than the previous 3 years.
It appears to be interacting with onemap.sg data so you get to see a map whereas a long time ago it was all text based reporting.
There are property agents that are diligently recording down all this information and perhaps you have even received a mailer from one of them.
I really feel that property prices, especially Condo prices, are getting a bit ridiculous. Developers try to justify the prices by claiming they have added plenty of luxury extras, but seriously, just give me a grass lawn and shady tree over a marble fountain anytime.