The franchisee shall not sell or transfer its plant or system nor transfer any rights under this franchise to another without town approval. No sale or transfer of the franchisee's assets used in the performance of this franchise shall be effective until the vendee, assignee or lessee has filed in the office of the county clerk and recorder an instrument duly executed reciting the fact of such sale, assignment or lease, accepting the terms of the franchise and agreeing to perform all the conditions thereof. Such council approval shall not be unreasonably withheld and neither this section nor other sections of this franchise shall preclude the mortgaging, hypothecating or assigning of rights in the system, or the pledge of stock by the franchisee, for the purpose of financing. (1976 Code § 5.45.070)