Recent immigration trends and a general reluctance on Europe's part to have "borders" (an archaic and unfair construct, I know) would be top of my mind if I were considering investment in European RE. I'd be at a terrible informational disadvantage and have to do research...
Good luck.
Seems like the author is pushing RE crowdfunding 'cause he's an RE crowdfunding guy.
I am just supporter of the idea, that everybody has right to earn with the help of investing in real eastate micro-sums