I'm actually interested to know how much full-time photographers are paid in Singapore. However, this really depends on the field of photography.
I assume the thread-starter intends to enter the industry. Generally, photographers tend to make money if they are in a niche or fairly closed market, for example, news journalism, high end fashion, commercial, etc. If you intend to do event (or some call public relations) photography, this field may be is as good as redundant. Look around at the massive number of people buying DSLRs and calling themselves photographers -- that's your answer.
In Singapore, I would say that the safest full-time job as a photographer would be with a news agency such as The Straits Times. Such photographers are employed and paid, I believe, a constant salary. (Some years ago, I was told they start at about $1600.) They don't have to promote or market themselves to earn $$.
If anyone wants to do fashion/commercial photography full-time on your own, you must realise that this photography business relies a lot on self marketing. You may be excellent in your work but if you can't promote and sell yourself and your advantages, you will end up sitting on your sofa all day doing nothing. You must also realise that this craft is a very subjective one. Your style may not appeal to all subject to individual tastes and cultural differences, and you must keep yourself updated with the latest imaging trends.
I'm not a high-flying successful photographer but I'm in the industry long enough to see/hear/know why some photographers close up shop. If you can peel away the facade, get into the deepest parts of their studios, you will see that many of them worry where their next pay check is coming from. The reality is that many don't know. The numbers are simple -- few succeed, many fail. We hear of success stories, but we don't have seminars and workshops for failure stories.