With the Estate Agency Affairs Board (EAAB) in Johannesburg.  Upon registration, the EAAB issues the agent with a Fidelity Fund Certificate (FFC), which must be renewed annually.  It's illegal to practise without having been issued with a FFC. 

Contrary to what some people think, letting agents, business brokers, and "showhouse sitters" must also be registered with the EAAB.

In addition, an estate agent (and estate agency firm) which collects rents or levies must register with the Council for Debt Collectors (CDC), and this registration must also be renewed annually.  The government has recently been asked to exempt estate agents from registration with the CDC, but until such time as this has been granted, registration remains compulsory for those who collect rents or levies.

For further information, and application forms, visit the EAAB website (www.eaab.org.za) and the CDC website (www.debtcol-council.co.za).