What's the starting pay for a NUS FASS graduate ?

The answers are limitless actually.

since you may have people who become a property agents as a NUS FASS graduate and earn millions

or you may have those who become teachers and earn 3-5K

so there isn't a correct or wrong answer

I think this highly depends on your course, as well as the industry you apply for!

I have friends from FASS drawing a starting pay ranging from $3000 to $4200 a month.

Note that my sample size is rather small; there are probably fresh grads from FASS drawing a lower/higher starting pay!