I was taught in yeshiva that as a young man, Rambam just studied Torah and was supported by his brother, who was a jewel merchant. Then his brother died at sea, so Rambam became a physician.
Some therefore claim that when the Rambam wrote that it is absolutely forbidden for one to say "I will just study Torah and not get a job", that doesn't apply if your family supports you, because the Rambam did that!
Recently someone told me that no, Rambam was never a "professional Torah student." His brother did the hard work of sailing the seas to obtain the jewels wholesale, and Rambam had a fairly calm job retailing them -- but he was still working.
Does anyone have sources on this, please?