During the Depression (the one started in 1929) my grandfather went down to
the bank and bought the mortgage on his farm for about 7 cents on the
dollar.

So why 700 Billion $ and all these laws?

Wouldn't it be better (and simpler) to give people with mortgages the
opportunity to buy their mortgage for pennies on the dollar?

It may not fix every problem, but it would certainly be of great benefit and
reduce the cost of housing.