Good morning Lynda,
Thanks for getting in touch, please see below the information that you will receive in your final information for your trip.
The national currency of South Africa is the Rand (R). We recommend you take local currency and Pound Sterling travellers’ cheques which can be changed at exchange bureaux. US Dollars are not allowed in South Africa.
MasterCard and Visa are preferred. American Express and Diners Club are also widely accepted. ATMs are available in all towns, cities and shopping malls and most petrol stations, and accept international cards. Almost all hotels, shops and restaurants, and even national parks and game reserves, accept credit cards. They are rarely accepted at petrol stations, however.
Money can be changed at banks, bureaux de change and some hotels. Proof of identity may be requested; therefore, it is advisable to carry a passport. Visitors are restricted to bringing in and taking out a maximum of R5,000 in cash.
I would advise changing 400 Rands back to avoid any problems upon arrival. However as stated above, there are plenty of ATM's so you can withdraw more at any time,
I hope this helps,
Kindest,
Ben