(a) An insurer may invest in:

(1) Bonds, notes, or other evidences of indebtedness, in addition to those eligible under Code Section 33-11-20 (corporate bonds and debentures) which are secured by first mortgage or deed of trust or deed to secure debt upon fee simple, unencumbered improved or income-producing real property located in the United States or Canada, including leasehold estates in such real estate:

(A) The loan or loans when made on a single-family residential dwelling shall not exceed 80 percent of the value of the real property or leasehold securing the real property; nor shall the loan or loans exceed 75 percent of the value of other real property, as determined by competent appraisers, unless guaranteed or insured by the secretary of veterans affairs or insured by the secretary of housing and urban development as provided in paragraphs (3) and (4) of this Code section;

(B) Unless the loan is guaranteed or insured by a governmental agency, as provided in subparagraph (A) of this paragraph, the appraisal must be certified by two or more company officers, or qualified employees, or by two independent appraisers;

(C) No loan made or acquired by an insurer which is a participation or a part of a series or issue secured by the same mortgage or deed to secure debt or deed of trust shall be a lawful investment under this Code section unless the entire series or issue which is secured by the same mortgage or deed to secure a debt or deed of trust is held by the insurer or unless the participation held by the insurer in the mortgage or deed to secure a debt or deed of trust gives the insurer substantially the rights of a first mortgagee and no other participant in such mortgage or deed to secure a debt or deed of trust holds a senior participation therein;

(D) All loans secured by leasehold must provide for amortization payments on principal at least once in each year in amounts sufficient to amortize completely the loan within a period of four-fifths of the term of the leasehold, inclusive of the term which may be provided by an enforceable option of renewal, but in no event exceeding 35 years;

(E) For the purposes of this Code section, real estate shall not be deemed to be encumbered by reason of the existence of taxes or assessments that are not delinquent, instruments creating or reserving mineral, oil, or timber rights, rights of way, joint driveways, sewer rights, public utility easements, rights in walls, nor by reason of building restrictions or other restrictive covenants, nor when the real estate is subject to lease in whole or in part whereby rents or profits are reserved to the owner, provided that the security created by the mortgage or trust or security deed on the real estate is a first lien upon the real estate and that there is no condition or right of reentry or forfeiture under which the lien can be cut off, subordinated, or otherwise disturbed;

(2) Purchase money mortgages or like securities received upon the sale or exchange of real property acquired;

(3) Bonds, notes, or other evidences of indebtedness which are secured by mortgage or deed of trust or deed to secure debt on real estate or an interest in real estate in the United States, if payment of such indebtedness or part of such indebtedness is guaranteed or insured by the secretary of veterans affairs in accordance with the Servicemen's Readjustment Act of 1944, as amended;

(4) (A) Bonds, notes, or other evidences of indebtedness which are secured by mortgage or deed of trust or deed to secure debt insured in whole or in part by the secretary of housing and urban development under the terms of the National Housing Act, as amended, or any other loan guaranteed by the federal government or its instrumentalities.

(B) Any portion of a loan referred to in paragraph (3) or subparagraph (A) of this paragraph, which is neither insured by the secretary of housing and urban development nor guaranteed under the Servicemen's Readjustment Act, as amended, is subject to the same provisions as apply under this article to uninsured mortgage loans.

(b) Nothing in this Code section shall be deemed to prohibit an insurer from renewing or extending a loan for the original or a lesser amount where a shrinkage in value of the real estate securing the loan would cause its value to be less than the amount otherwise required in relation to the amount of the loan.