It should be made illegal for banks to persue the owners for a remaining mortgage balance after a re-possed property has been sold at auction for a below market price. The bank negotiated an interest rate commensurate with the risk at the start of the contract. So how can they then be justified in persuing customers for the balance of the mortgage.
In the current circumstances the law allows them to record the debt still owed after repossession as part of their assets and they can therefore re-posess properties without loosing a penny.
If this was made illegal, then they would have every incentive to negotiate a temporary affordable rental with the tenant. Title of the house could pass to the bank during this time and the tenant given a right of residence, until they could re-mortgage or sell the property at it's market value.
I believe that this would result in less impact on society such as emergency accommodation from councils, less social security benefits which we all pay for etc.
Tenants would be grateful for support and probably loyal customers of the bank in the future.