There is no minimum residency requirement in South Africa. Some marriage officers like to meet with the couple the day before the wedding though, so you will need to discuss this with your priest or celebrant ahead of flying out.
Applying for a marriage licence:
There is no such thing as a marriage licence in South Africa. You will be asked to complete a simple form by your marriage officer called a B1-31. This is usually done when you arrive in the country.
For this you will need these essential documents:
* Sometimes a birth certificate is also requested
Additional documents if relevant:
* Divorce certificate
* Death certificate if widowed
The South Africa Marriage Act states that if you plan to marry outdoors, it's a good idea to repeat the legal part of the ceremony indoors to avoid any doubts wether you are formally married. However, as long as your marriage is solemnized by a marriage officer, the courts are not readily inclined to declare a marriage invalid, simply because it was held in the wrong place.
But if you are marrying outdoors, you will be asked to sign the register in a location that has a roof and an address, which invariably means that you will simply sign on the dotted line inside the hotel after your beach ceremony.