Portal services are administered by AppFolio Inc & CINC Systems. Transactional service fees charged, paid to, or collected when using a credit or debit card in the portal are retained by AppFolio & CINC exclusively. Cornerstone does not receive any portion of transactional fees assessed by AppFolio. We recommend using the free eCheck option to avoid a service charge when making payments or depositing funds into your Cornerstone account.