The IMF had a report out yesterday on the sale of citizenship. This is the current state of play on this issue:
As the IMF say:
The wealthy, especially in emerging market economies, see buying citizenship or residency rights as a means of greater global mobility (visa free travel in many countries), tax planning, and family security.
As is noted, inward investment is the usual price to pay. But, and it is a very big but, housing can meet the criteria in some cases making the whole thing pretty nominal.
What is sad to see is that so many large states, the UK included, are willing to sell sovereignty in this way. This was so recently an issue in the referendum vote. What the IMF makes clear is that the concern about migration in the UK and many other states is deeply prejudiced.
Not all are equal when it comes to choosing a home, let alone a place that might provide the protection a person needs, and that to me seems like a straightforward affront to human rights.