They're highly popular for turnkey rental properties because qualification is primarily based on the income generated by the property itself rather than the borrower.

I predict that the substantial home price cost savings and greater control they enable the buyer to have will make them grow in popularity.

If any of these do not pan out, the turnkey company feels the weight of assuming that risk. 

https://www.biggerpockets.com/blog/short-term-rental-loans-a...DSCR Loans: Terms to Know When Working With These Popular Rental Loanhttps://www.biggerpockets.com/blog/dscr-loans-terms-to-knowWhat’s Next For DSCR Loans?

Beside investing their own cash on the same terms, the sponsors return should be heavily weighted toward “carry” (receiving the bulk of their return as sponsor in the form of an interest in the property rather than cash) with that carry subordinate to the investors receiving their investment returns PLUS a minimum annualized return.

@Eric Andersen definitely put weight into what @Michael Baum wrote and do your own research on the city regulation/zoning.

They are investor friendly and popular amongst wholesalers.

A reliable property manager and CPA are worth their weight in gold, especially when you’re managing remotely.If you’d like to chat more about what’s worked for my clients or have questions about specific markets, I’m always happy to share insights.

https://www.biggerpockets.com/blog/short-term-rental-loans-a...DSCR Loans: Terms to Know When Working With These Popular Rental Loanhttps://www.biggerpockets.com/blog/dscr-loans-terms-to-knowWhat’s Next For DSCR Loans?

As to gurus, being popular, attractive, witty, friendly, or just lovable doesn't mean they are ethical, lawful, correct or are qualified.Qualified: Now, that is an interest aspect for a teacher or instructor.