There are plenty of legit REIT opportunities out there, but if there's ads promoting it on facebook then it's safe to assume there's more money being made in advertising/promoting those specific schemes then actually investing in them.
I tend to always view any of that stuff as, if it's being promoted to me in a public space (TV, Facebook, etc...) then either A) The money is being made in sales/promotion of the product, not the investing in it, B) The meat has already been so taken off the bone that you're getting scraps at best, or C) The payout structure is such that you're taking on the greatest amount of risk but also the last in line to get paid on profits.
I know a lot of guys that do very well in that space, and very few of them need to publicly solicit.