Well, I'll give credit to Carlton Sheets for one thing: he inspired lots of people to get involved in real estate investing, even if his stuff was bs. I was among them. I bought his course, started it, said "That's crap, it will never work" but went out and educated myself on buy and hold because I was bitten by the bug.
Armando Montelongo must be alive and well and selling lots of mentorship programs, because I have two current customers doing deals as a result of his programs. They are thin deals, but ok for a first deal. One of them found me here on BP and his project is coming along nicely, looking good.
As for Than Merrill and Paul Esajian, I have a great deal of respect for them, actually, and know them both from multiple points of contact. Yes, they are selling courses, bootcamps, mentorship programs, etc, but I consider them to be among the best of the guru's, and I work with a number of investors who are in their mastery program. I don't like the hard sell, but their stuff is good. Of course real life is never like the seminar, but I think they do the best in preparing the students for reality. Out of the guru's that is.