No insurer shall commence business under this chapter until it shall have procured bona fide applications for insurance therein together with the first premium in cash from at least 300 eligible persons for each class of risk as defined in section 6406 which the insurer undertakes to write; nor until the secretary and treasurer shall have given good and sufficient bonds to the insurer to be held by the president of the insurer, for the faithful performance of their duties, which bonds shall each be in amount at least twice the amount of money liable to come into the hands of such officer at any 1 time, said bonds to be approved by the commissioner; nor until the commissioner, after receipt of satisfactory proof as to compliance with these and such other requirements as he shall deem essential, shall have issued a certificate of authority to such insurer, then, and not before, the insurer may issue its policies of insurance.