Most lawyers will give an initial consultation for free.
The law here is quite stringent in terms of divorce.
First, if you haven't live in Singapore for 3 years you aren't eligible for divorce.
You also have to have been separated. As in not living in the same house, for 6 months.
If this is the route you intend to go, it may be easier to go back to your home country. The waiting period may be less and, afterall, if you AND hubby are expats, why would you want the legalities to be in Singapore?
This is all IMOHO...and I'm not a lawyer - just someone who has been there.