The commission may provide for the issuance of bonds of the commission for the purpose of refunding any bond then outstanding, including the payment of any redemption premium thereon and any interest accrued or to accrue to the earliest or subsequent date of redemption, purchase, or maturity of the bonds and, if deemed advisable by the commission, for the additional purpose of paying all or any part of the cost of constructing and acquiring additions, improvements, extensions, or enlargements of a project or any portion thereof. The commission may issue refunding bonds to refinance its indebtedness only if the commission finds that the refunding is in the public interest due to the terms or conditions of the refunding, including, without limitation, lower net interest cost, maturity or maturities, call provisions, or similar terms and conditions.