For 2 people ( i am assuming husband + wife)

Housing: You have 3 options -
1) Rent 2 room HDB house in North (Woodlands, Sembawang, Marsiling - these are cheaper areas), $1600 - $2000 (excludes, PUB etc., which is approx. $50-100 per month)
2) Rent a master bed room in a HDB house $800-$1000 (includes aircon, tv, internet)
3) Rent a condo master bed room / room (but will be very expensive) - almost same as (1) and still you might not be able to use the kitchen.


Food:
1) If you rent 2 rm HDB house in north, then most of cooking can be done at home.
2) If you rent only only a room, then it is upto the contract whether you can use the kitchen or not. Even if the owners allow, most of the time, it will be light cooking - tea, maggie, etc.
3) Food in hawker centers are cheap. Will cost between $3 to $5 per meal. Most of the time, I get my dinner packed for $3.4 (includes rice, 2 non-veg and 1 veg).
4) Bread costs around $1.1 ; eggs $2.5 etc.

Transportation:
1) You will be using MRT/bus. It will depend on how much distance you need to travel from your home to work area. Take an average of $100 per month.
2) If you take cabs/taxis, of course it will be higher.
I mostly spend around $70 for Bus/MRT and another $50 for cabs (when i am running late).

Phone:
1) 3 service providers - singtel, starhub or M1. Almost same packages costing same.
Around $40 per month (depending on your usage - it can go higher).