The capital stock shall be paid in cash within twelve (12) months from the date of charter or certificate of organization, unless the commissioner of insurance on proper showing shall grant additional time for the completion of the sale and payment of said stock; and no certificate of full shares shall be issued until paid for in full. No policies shall be issued until an amount equal to the minimum required by law shall have been paid into the company and a license to engage in business has been issued by the commissioner of insurance.