So any source of income must guarantee a living wage?
Yes. Anything less is some percentage slavery, as defined as the percentage by which it falls short of providing a living wage. This problem can be solved by eliminating tax loopholes and cutting the defense budget, then using the money to implement minimum guaranteed income. We will also have to shitcan the ACA and implement a national single-payer health care scheme from which the wealthy can not simply opt out by having a superior plan. (They're free to buy more health care, but not to not pay their share of national health.) Under such a system, employers would never have to pay for employees' health care, nor would they have to pay a minimum wage. They would be free to pay any amount someone was willing to receive to do the job, or even charge someone to do the work for personal fulfillment or educational purposes.
If you have an alternate proposal which does not amount to slavery, I'm interested.