s 38 Certain alterations of regulated agreements to be of no effect
38. Where a regulated agreement is signed by or on behalf of the hirer, any alteration of, or matter added to, the written document that contains the terms and conditions of the agreement after the document was signed —(a) if the alteration is an alteration of any of the matters required to be specified, contained, or set out in the agreement by section 3(3)(c) to (e); or (b) if the additional matter is a matter required to be so specified, contained, or set out or affects any matter required to be so specified, contained or set out, has no force or effect unless the hirer or his agent has consented to the alteration or the additional matter by signing or initialling in the margin of the agreement opposite the alteration or additional matter.