There's been an ubiquitous edition of articles on how you should take care of your expenses, but there were little mention of how you should also be taking care of your income, especially bad income.
The bad income is of course very subjective and it differs in definition from one individual perspective to another.
One way to differentiate "bad" income from "good" income is to quantify it through how some income is taxed more favorably than others.
For the majority of the people, income derived from employment or trade business are generally considered "bad" income because they would attract a chargeable tax to that income class. This is exception to employment income that you derived overseas assuming you are seconded there for a few years (you are subjected to the overseas tax legislation though).
Property income that you derived from renting out your premise would also be subjected to income ......