May I know roughly what are the charges for a babysitter?

This article provides a good comparison of the different childcare options and their costs that you can consider: http://blog.moneysmart.sg/family/childcare-options-in-singapore-which-one-should-you-choose-and-how-much-does-it-cost/ In the list are Infantcare/childcare centres, Babysitter, Amah/Nanny. You can consider the different options based on your needs.