Some of the requirements of maintaining an investor's visa are proper accounting done by a registered accountant in brazil, and tax filing every three months.

the foreign investor must annually renew his of her ID card at the Federal Police - At that time, must attach a copy of the last payment form of the Fundo de Garantia do Tempo de Serviço - FGTS and an employees' report.

the Fundo de Garantia do Tempo de Serviço - FGTS, is a system used to collect funds towards employee's state benefits, and more information on the matter can be found this link.