How do you exchange your cryptos? You would need an account at a Singaporean bank. Then spend your savings in Singapore, and go back to India empty handed?
Well obviously there's going to be a level of trust seeing as recourse is narrower, just like any black market transaction. Maybe even some possibility of extralegal recourse. But people can and therefore will do it.
How would that work? Can't you just not donate the house, after they have given you their crypto?