When you sell your apartment and when you bought your house? I
know someone who just sold en bloc for 2 mil, then bought a new
house at YCK 1830 sq ft for 1.7 mil. So my guess is your house,
either you bought quite a while ago, or is 2nd hand?
Anyway when property prices increase, property tax increase. More
sales = more stamp duties to be paid. Wonder where all these money
went...