Of course you can buy/rent a place easy with an S/O's allowance, but you have to remember something.........you CANT compare HK to where you are coming from.
If you intend on living in a 4000sq ft house, 3 storey high with garden and on top on The Peak.........then the answer is no.
That being said, your housing allowance will cover you easy for a nice new flat around 1000sq ft, depending on the loc of course.
Flats range from HK$2m for 700sqft to.........anything up to HK$30,000 per sq ft...........depends where you want to live really
got to remember one thing, its a free flat in HK, one of the most expensive property markets in the world..........and CX is paying for it.