The simplest way to generate income is the old society's triathlon.
No technical skills required, significant income, and manageable risks.
That's right, in the eyes of the big bosses behind those businesses, the risks of brothels, casinos, and opium dens are completely controllable.
As long as you don't encounter a crooked-mouth youngster, a master in disguise, or a fierce dragon crossing the river, it's pure profit.
What is truly high-risk, high-return business?
It's what Foreigners play with in financial securities, banking insurance, and pharmaceutical military industries.
It has nothing to do with whether you have power or status; if you don't understand the field, you'll pay an intellectual tax no matter how much money you invest.
You'll have no idea who to approach to retrieve your money.