Same here. I phoned airbnb, they said they are not sure about the bank charges, and they advise me to check with the bank.
So I phoned standard bank and their explanation seems ridiculous to me. Says that if the company is registered overseas, meaning if it’s not an SA registered company, you will get charged an international transaction fee every time you made a payment. In this case, airbnb is an oversea company, so standard bank charges us…