I will visit Argentina in April. I was interested in visiting Iguazu Falls and started searching through Expedia, Destina, etc. All quotes were unbelievably high.

I decided to post a question on Lonely Planet Thorn Tree and got the answer, which I will give you for the same price I've bought it: the Argentinean government charges up to 3 times more from foreigners. According to these sources, only nationals can buy discounted tickets. It seems true, as I checked one of the airlines website and found a very good price, but the catch was at the bottom of the page, where the buyer should write the number of his/her Argentinean ID, along with the Department that had issued such document.

As a result I changed the duration of my stay (first stop in a RTW award trip) to two days, prefering to patronize another country that treat visitors with more consideration with some extra days of my time and spending.