If you borrow $500k and the Aussie currency drops 10% against the currency you borrowed from you owe $550k. The best time to borrow overseas is when the Aussie dollar is low because there is more upside potential than downside. However with the Aussie dollar so high now it is not a good time to borrow overseas. It is a good time to send money overseas though, i.e. the Singapore banks offer high interest rates and the Aussie dollar is strong against the Singapore dollar.
