Asking about the cost of marriage is like asking about the cost
of the car - it very much depends on oneself, how elaborate one
wants the wedding to be, etc. I know of cases where weddings cost
just a few thousand....and other cases where they were over
S$100k.
Mine was 6 years ago and we managed to break even from the angpows
collected (fortunately for us, mainly due to some generous
relatives). The angpows even managed to pay for our short
honeymoon.
To be complete, you'll also have to take in the costs not directly
associated with the wedding - (eg. buy house?).
The real cost of a marriage, however, is dealing with spouse and
in-laws. 
This one
is life-long.... oooooh, you'll find this out sooner or later, when
the honeymoon/fairytale period ends.
