Did Communists take over South Africa?

Not so easy to answer. Yes and no? Perhaps more no than yes?

Jenkins: When Communists Took Over South Africa

[...] Two decades later Mandela's ANC has indeed become a party of revolutionaries turned business owners and financiers.

In their well-researched 2012 book "Who Rules South Africa?" the journalists Martin Plaut and Paul Holden found that three-quarters of cabinet members had outside business or financial interests as did 60% the regime's 400 members of parliament. They also report that, in 2011, South Africa's auditor-general found that in the impoverished Eastern Cape, ancestral home of Mandela and many other top ANC leaders, 74% of government contracts went to companies owned by state officials and their families.

At the moment, South Africa's likeliest next president is Cyril Ramaphosa, a former militant union leader and Mandela protégé who serves as ANC deputy president. According to Forbes, Mr. Ramaphosa is worth $625 million—three times Mitt Romney's wealth. [...]

If South Africa continues to have free elections, I wonder how long Ultra-rich ANC members will continue to get elected?

I'd posted exactly one year ago, about a split in the ANC being a possibility. This article explains some of the history and reasons why that may happen.