Greek Philosophers like Socrates, Plato, etc did teach classes, so were they paid to do that? Was it the governing head of their times giving them money, goods, housing, etc because of what they were doing? In their time of not teaching did they still make money? What are the known "logistics" of Greek Philosophers paychecks?
Also it should be said that Greek Philosophers like Diogenes didn't live in lavish places, but that was more out of his choice because he followed cynicism. But could he have earned money and simply chose not to do that? Alexander the great did say to Diogenes if he needed anything that he could ask, and just turned him down.
Apologies for the late response. Every philosopher was different and had their own ideas about money and monetary gain, so I will have to give a relatively broad answer. Generally, many Greek philosophers made their money from tutoring or teaching their students. They would find patrons who were willing to pay them for their services. In Epictetus' Discourses he compares the role of a philosopher as something akin to a caretaker of the soul. Others refused payment for their services, and only accepted donations in the way of food and lodgings. Plato writes in Apology and Symposium that Socrates denies any payment for teaching. Socrates even goes as far as to claim that his poverty is evidence that he is not even a teacher at all. A lot of philosophers in Ancient Greece may have come from Aristocratic backgrounds, allowing them to self fund their philosophical endeavors. All in all, there were a plethora of different ways that philosophers got by, but the most common way was tutoring/teaching and finding a wealthy patron who was willing to pay for their services.