(1) Any savings and loan association may charge, contract for, and recover such rate of interest as may be provided in the notes or other evidences of indebtedness taken by the association. Notes secured solely by the pledge of shares and notes secured by real estate mortgages repayable upon the sinking fund plan shall be nonnegotiable in form, and all other notes, including those insured by the federal housing administrator and those taken in connection with loans to veterans under the provisions of the "Servicemen's Readjustment Act of 1944", may be either negotiable or nonnegotiable in form.

(2) A substantial portion of the business of all associations shall be devoted to the acceptance of savings deposits from or the sale of their shares to their members and the lending of those funds to their members as set forth in section 11-40-103 and otherwise in articles 40 to 46 of this title, but associations may also purchase loans of a type which they are permitted to make and sell loans with or without recourse so long as such purchase or sale of loans is conducted as a part of and in connection with the other permitted business activities of an association.

(3) Each mortgage loan sold by an association may be sold with or without recourse and, if under a contract to service the same, shall be sold on a basis which will reimburse the association adequately for the cost of such servicing. All sale and servicing agreements shall be in writing and on file in the association.

(4) No interest that may accrue to an association shall be deemed usurious, and the same may be collected as debts of like amount are now by law collected in this state.

(5) No law of this state limiting interest or interest rates or the compounding of interest shall apply to any graduated payment mortgage or deed of trust made to individuals, or any mortgage or deed of trust to individuals where periodic disbursement of part of the loan proceeds is made by an association over a period of time as established by the mortgage or deed of trust, or over an expressed period of time ending with the death of such individuals, including but not limited to mortgages or deeds of trust having provisions for adding deferred interest to principal or otherwise providing for the charging of interest on interest.