No problem with the time - Xmas is not a big holiday here (CNY is much bigger). But finding a place within two weeks may be tricky, depending on how fussy you are.
http://www.gohome.com.hk for rental listings if you want to get a place by yourself.
Flatsharing is quite common amongst younger expats. Various listings magazines and a website I'm not allowed to mention here have ads. I guess the chance of it working is much the same as flatsharing anywhere.
Normal rental agreement is for 2 years but with the tenant able to exit with 2 months notice which can be given after 12 months (so minimum commitment is 14 months). Deposit is normally 2 months. All of this is negotiable - but shorter tem leases tend to be expensive. Agency fee (if you use one) is normally half a month from each of tenant and landlord, but also negotiable.
Renting a serviced apartment is also possible.
Whether you get the deposit back depends on what condition you leave the place in! In general, if you get it cleaned when you leave you can get it back with not much hassle.
do most expats share or rent a flat on one's own? 
