if u are very cash rich, then buy a property makes sense because you are getting 3% interest rate on your cash and u can get 3% actual rental yield on your property (even if you stay yourself, look at it from a rent to yourself at market rate view).
if u are going to take a loan, then renting makes sense, unless your view is that property price has more than 66% chance of going up within the next 2 years. any other chances, it'd make sense to wait for the window then buy.
remember, in buying, u are not getting an option for the upside of the house price, u are just hitching yourself into a contract where if it goes up u win, if it comes down u lose, and u are paying for that option through your interest paid, agent fees, etc.etc.
also to note, all properties in hk has a limited holding period up to 2047 (50 years after 1997 handover).
practically, everyone thinks that chinese govt is not going to change much of the legistration, but technically they can change and void all commercial contracts previously signed (right ?).
so as u go on, in 15years time, banks are not going to offer loans for properties unless the chinese govt says they will extend the lease period of all properties. it might be a tricky situation but now everyone is pretending the problem doesn't exist (esp those with a property or have interest in property).
my view is, unless the communist govt comes out and officially state the rules after 47, banks are going to give lower and lower loan quantum and shorter and shorter duration, this will have a bad effect on overall property price over long term. someone wld pressure the govt in china to do something, but they would not want too much of a wealth disparity in hk and they might use this oppt to let the property market correct somewhat.
all my speculation..