A lawyer or a law firm may sell or purchase a law practice, or an area of law practice, including good will, if each of the following conditions is satisfied:
(a) The seller ceases to engage in the private practice of law, or in the area of practice that has been sold, within the State of New Hampshire;
(b) The entire practice, or the entire area of practice (subject to the clients’ rights under Rule 1.17(c)(2)), is sold to one or more lawyers or law firms;
(c) The seller gives written notice to each of the active and inactive clients of the practice or practice area being sold regarding:
(1) the proposed sale;
(2) the client's right to retain other counsel or to take possession of the file; and
(3) the fact that the client's cons