Rule 32:1.2: Scope of Representation and Allocation of Authority Between Client and Lawyer
subparagraph (c) “A lawyer may limit the scope of representation if the limitation is reasonable under the circumstances and the client gives informed consent.
(1) The client’s informed consent must be confirmed in writing. . . . 
(2) If the client gives informed consent in a writing signed by the client, there shall be a presumption that:
(i) the representation is limited to the attorney and the services described in the writing; and
(ii) the attorney does not represent the client generally or in any matters other than those identified in the writing.”