140.—Except where otherwise provided for in this Act, a creditor or an owner—

(a) shall not, in any agreement—

(i) exclude or restrict any liability imposed on any person or any right conferred on a consumer, or

(ii) impose any further liability in addition to any liability imposed on a consumer,

by this Act, and

(b) shall not be entitled to enforce any agreement (other than a housing loan) which so excludes or restricts any such liability or imposes any such further liability.