Clients must sign a normal hourly fee agreement. Always. After that you can consider the agreement in terms of the Contingency Fees Act and/or common law contingency. Do not be stupid enough to simply try a sign a common law contingency agreement when there are disputes as to how Courts may treat them. If you want to work on a contingency basis then get your clients to sign 3, yes 3 agreements:
*a common law contingency agreement
*a statutory agreement as per the Act
*an hourly fee agreement
If nothing else an hourly fee agreement will back you up when all else goes wrong. Remember in terms of the Lyons vs D'Abro case to attach, and get the client to initial, the actual tariff.
Our Courts have held that attorneys without proper fee agreements must expect to find themselves in the same situation as a person who loans money without getting people to sign acknowledgments of debt. Don't let that be you. You have been warned!