any interest and penalties due) and the factual and legal basis for such amounts being due with sufficient specificity that such basis can be understood by a reasonable person who is not a tax professional reading the notice. The final notice shall be sent by certified mail, return receipt requested, to— (1) the address last provided by a registered seller, or (2) the best available address to a person who is not a registered seller. (e) Confidentiality of Tax Information (1) In general All reports and report information (related to any internal revenue law) shall be confidential and except as authorized by this title— (A) no officer or employee (including former officers and employees) of the United States, (B) no officer or employee (including former officers and employees) of any State or local agency who has had access to returns or return information, and (C) no other person who has had access to returns or return information, shall disclose any report or report information obtained by him in any manner in connection with his service as such officer or employee or otherwise. (2) Designees The sales tax administering authority may, subject to such requirements as the Secretary may impose, disclose the report and report information of a person to that person or persons as that person may designate to receive said information or return. (3) Other sales tax administering authorities A sales tax administering authority may impose, disclose the report and report information to another sales tax administering authority. (4) Incompetency A sales tax administering authority may, subject to such requirements as the Secretary may impose, disclose the report and report information to the committee, trustee, or guardian of a person who is incompetent. (5) Deceased persons A sales tax administering authority may, subject to such requirements as the Secretary may impose, disclose the report and report information to the decedent’s— (A) administrator, executor, estate trustee, or (B) heir at law, next of kin, or