In Mendoza, I exchanged dollars on the blue market at the rate of 8 pesos to the dollar. The official exchange rate given by banks, hotels, and credit cards is around 5 pesos to the dollar. The unofficial blue market can be found by walking south on Sarmiento until San Martin. Turn left (east) and walk on the south side of San Martin about 1.5 blocks. Men are standing on the street saying "cambio". Agree on a rate, walk into an office, and exchange dollars for pesos. Also many stores will negotiate dollars. My experience was any where from 10% off to giving the rate of 8.3 pesos for each dollar. The Buenos Aires Herald publishes the blue dollar rate about once a week. The local Mendoza paper also carries the blue dollar/parallel rate.
Since the blue dollar/ parallel exchange market is not officially sanctioned by the government, the exchange area and the rates may disappear.
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