Any company organized or operating under this chapter whose business is limited by law or by its charter to 1 or more counties may provide in its charter or by amendment to its charter for assuming reinsurance from other companies on property located anywhere within the state: Provided, however, That no reinsurance shall be accepted of a different kind or on a different class of property than the company is by its charter permitted to write direct. The company ceding such reinsurance shall not, by virtue of such reinsurance, become a member of the company assuming the reinsurance nor shall the ceding company assume any contingent liability for assessment unless otherwise provided by written agreement.