This subseries contains invoices for items purchased by the Heritage Book Shop. Not all years have a complete range of alphabetical files. A few years are missing, and the invoices available do not run up to the present.

This subseries contains files relating to FBI and IRS investigations, forgery papers, bad debt files, and other lawsuits.

This subseries contains correspondence of various types, including client correspondence, client inquiries, correspondence related to membership and leadership roles in the ABA (American Booksellers Association) and ABAA, joint sales correspondence, interest queries, appraisals, and financial correspondence. Joint sales correspondence includes letters to and from the Heritage Book Shop and other booksellers with whom they sold books jointly, including Kenneth Rendell.