Eunice, @bsolute cleaning part time maid do cleaning and ironing:
http://www.absolutecleaning.com.sg/parttimemaid.html
I am using them for 4 months now,
so far no problem and always on time.
sassy_gal, beware of those $10 per hour one because most of them are not licensed.
I suggest you read this article:
http://www.auntiecleaner.com.sg/articles/6-reasons-to-stay-away-from-freelance-part-time-maid.html
For one time cleaning you can try Singapore Part Time Maid:
http://www.part-time-maid.com/articles/where-can-i-find-once-off-house-cleaning-service.html
They are quite reliable.