This Part deals with the extent to which the parties to a contract to which this Act applies may by reference to contract terms oust or vary the right to statutory interest that would otherwise apply when a qualifying debt created by the contract (in this Part referred to as “the debt”) is not paid.

This Part applies to contract terms agreed before the debt is created; after that time the parties are free to agree terms dealing with the debt.

This Part has effect without prejudice to any other ground which may affect the validity of a contract term.