John Beck was a guru back in the early 70s who did a lot of small time (self promoted ) stuff with tax liens/deeds, particularly in California.  

I know that bigger pockets kind of promotes rentredi.

I also believe, but cannot yet prove that Spark has earned remuneration for putting together the group of investors in that if they are buying a $50,000 share from a promoter they remit some amount less than that and receive the full share giving them a "share" of the LLC they created to hold everyone's funds.

Note investing is something that gets promoted a lot.

I see the same with note investors and people writing books and doing coursesI can name many people who now sell courses in a different strategy (whatever is hot) because they just bounce around promoting a lifestyle “live your life and earn $25k/mo passively with (insert investing type).

Most leases are for 6 months only and they do run promotions like first month free rent.- I got used washer/dryer from them.

I am in by no means promoting these syndication though haha.... in the last two months, i found those two deals , one in MF and one in industrial, the key thing that makes them attractive is that the new sponsor can assume the 3-4% loan from previous owner. 

That is how it is promoted in the videos on youtube. 

More educational and networking rather than promoting products and services.

In our experience, the S8 guru/scammers promote buying Class D properties and then renting them out to S8 voucher holders.It takes a lot of hustle and probably legally bribing the tenant with an appliance or two, to get them to move into a bad area.No telling how long they will stay either.