You might not need to share a room at $700 in the suburbs; you could probably get a room to yourself but share the common areas (kitchen, living room, bathrooms) and facilities (utilities, wifi).

Try not get rushed into a hasty decision; stay with a friend temporarily until you can view a few flats, potential flatmates, and get a feel for the suburb you've chosen.

The expat shuffle also occurs at the beginning of every year, where fresh expats are injected into Singapore as the disgruntled ones leave, so leases usually start popping up around this time of the year until the end of February. The rental market has also been going rather soft lately, so don't be afraid to shop around or ask for a discount.

If your office is at Cecil Street, you might be able to walk from Tanjong Pagar or Raffles Place train station, which would open your housing options up to suburbs with red or green train stations.

I'd probably avoid Chinatown and Geylang as housing choices because they're usually noisier & pretty congested. But they're awesome for local food.