Any assessment association which has accumulated and maintains the same reserve for liabilities that is required of a stock or mutual company organized to transact the same business, and either a surplus or a contingency fund equal to the surplus required to be maintained by a stock or mutual company organized to transact the same business, may, in its bylaws or policies, limit the liability of its members for future assessments, but such limitation shall not be less than the amount of one assessment equal to the regular assessment specified in the policy. All assessments shall be made by the board of directors unless otherwise provided in the articles of association or the bylaws.