Re. Spanish evictions: I wrote a scenario a few years ago.
Mass failure to pay mortgages or other debt leads to bank failures.
Bank failures in the old days meant depositors were wiped out, and lending stopped in the community.
Bank failures in more recent days meant the FDIC had to make mass payments to depositors. Lending still stopped.
Such mass FDIC payments would cause the FDIC to fail. Congress would have to enact a bailout.
From this point on it's anyone's guess, except that borrowing would be hard to come by, and probably have a political component.