I agree with everyone else here don't do it.

Notwithstanding safety issues, the border crossing itself can be a nightmare - processing times can be very long.

If you're willing to pay for a taxi, you might as well stay in a decent location in Singapore.
I can recommend the Four Points by Sheraton. It's one of the cheaper options out there but it's also a bit of a walk to the MRT (you can take a bus or taxi)
The other, slightly more expensive, but very conveniently located option is the courtyard.