(g) The term "contract" or "agreement," as used in this section, means the document creating the rights and obligations of the parties and includes any subsequent document making substantial changes in the rights and obligations of the parties. The term "contract" or "agreement" does not include any subsequent documents authorized or contemplated by the original document such as periodic statements, sales slips or invoices representing purchases made pursuant to a credit card agreement, a retail installment contract or account or other revolving sales or loan account, memoranda of purchases in an add-on sale, or refinancing of a purchase as provided by, or pursuant to, the original document.
The term "contract" or "agreement" does not include a home improvement contract as defined in Sections 7151.2 and 7159 of the Business and Professions Code, nor does it include plans, specifications, description of work to be done and materials to be used, or collateral security taken or to be taken for the retail buyer's obligation contained in a contract for the installation of goods by a contractor licensed pursuant to Chapter 9 (commencing with Section 7000) of Division 3 of the Business and Professions Code, if the home improvement contract or installation contract is otherwise a part of a contract described in subdivision (b).
Matters ordinarily incorporated by reference in contracts or agreements as described in paragraph (3) of subdivision (b), including, but not limited to, rules and regulations governing a tenancy and inventories of furnishings to be provided by the person described in subdivision (b), are not included in the term "contract" or "agreement."
(h) This section does not apply to any person engaged in a trade or business who negotiates primarily in a language other than English, as described by subdivision (b), if the party with whom he or she is negotiating is a buyer of goods or services, or receives a loan or extension of credit, or enters an agreement obligating himself or herself as a tenant, lessee, or sublessee, or similarly obligates himself or herself by contract or lease, and the party negotiates the terms of the contract, lease, or other obligation through his or her own interpreter.
As used in this subdivision, "his or her own interpreter" means a person, not a minor, able to speak fluently and read with full understanding both the English language and any of the languages specified in subdivision (b) in which the contract or agreement was negotiated, and who is not employed by, or whose service is made available through, the person engaged in the trade or business.