My home in the states is near the water, and as a result we get our fair share of snake visitors each year. Most are black snakes, which, after the initial shock, are relatively harmless. I actually purchased a pair of snake handling tongs to remove them from my yard. I have a shotgun (it's the US) should any copperheads (poisonous) come around. I hate them too, but basically they are just wild animals just doing their thing.
There is no 100% "snake proof" formula or material. Sulfur is rumored to work, but I can tell you from experience it does absolute wonders at destroying vegitation and very little at preventing snakes. Snake-a-way is an American chemical designed to keep away some varieties of snakes, but again, not a 100% cure.
Your best bet is to seal all possible entry points to the home. Check under sinks and make sure pipes do not have gaps, no holes in the cabinets, etc. Snakes have a very keen sense of smell and will follow the scent of food, so you may want to invest in a good quality trash can to keep down odors.
Any animal will attack if you hit it, corner it, piss it off, etc. Snakes are no exception, so please be careful.
My recommendation is to review the images of the different types of snankes found in Hong Kong so you can have a basic level of familiarization. I'm not sure how many are poisonous. Should you be confronted with one in your house, and are uncomfortable dealing with it, I'm not sure who you would contact. There are probably some rodent removal services that deal with snakes.
If the whole thing creeps you out, you can always move.