Slightly tangential, but I have talked to two escorts recently who have told me about their business and property portfolio. Buying flats from which to work, renting them to other WGs to cover costs, and then once financially sound, adding another flat, and so on. Once established they then became more flexible, continuing to rent to WGs, or renting as AirBnBs, or renting on a short-term lease depending on the financial climate at any time.
They were at slightly different stages in the process (one was in her late 20s, one mid 30s), but they had a solid plan that would allow them to retire by the time they were 40 and then live in comfort off the property income. I can't see either of them coming back after they quit.