Here a potentially interesting review on Crowdhouse (et al.): Crowdhouse: Critical Review, Risks, and 5 Alternatives - Le Bijou Invest.
It certainly explained some of the details to me (noob), such as risks; and also confirms what @hedgehog mentioned above, on incomes “leveraged through mortgage loan”.
p.s. Do not like the oversight of index funds / ETFs at the start, listing the investment options. 
Long story short - based on this article and its summary, now I don’t think I will dip my toes into this instrument.
In the best case, we will receive about 6% per annum; the income is not guaranteed, and we have our money locked in real estate for 5-10 years without the real opportunity to pull them out. The model is capital intense and also you take a mortgage, that doubles your risks.
Personally, I came to the conclusion that investment in Crowdhouse and similar services don’t provide a fair reward for the risk. During my career, I have been setting up deals that would yield 7% fixed returns (bonds), and also other deals without even buying the real estate but rather leasing it, that would give me up to 21%, and 13% – 18% in average.