Looking at the chart below we can see that the 64GB iPhone 4S costs $1,830 USD in Brazil. That is over twice the amount of the 64GB iPhone 4S sold in the U.S. which costs $849.
iG Economia has examined the price breakdown for the device and attributes 46.76% of the cost to import taxes. Foxconn has reportedly started production of iPhones in the country with shipments expected to leave the factory in January. Those devices should result in much lower prices for Brazilians since they wouldn't be subject to as many import taxes.
Chile's pricing is more reasonable than Brazil but a 64GB iPhone 4S will still cost about US$1425 through Vivo.