“The valuation of realty in Rio seems to test its own limits on a daily basis. In just six months, the average price for an four-bedroom apartment in Ipanema increased nothing less than 76%, to R$2.5 million. Smaller apartments and those in other neighborhoods also saw significant highs. A two-bedroom place in Flamengo had its average price increase by 44.8% between December of 2009 and this past June, to R$477 thousand, according to the Habitation Syndicate of Rio. 

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Factors such as a hike in income, the expansion of housing credit, the growth of Rio itself, the larger sensation of safety under the Pacifying Police Units (UPPs) and the drying up of land plots in the Zona Sul explain the extremely heated scenario. A little extra help came from the choice as Rio for the Olympics in 2016, announced in October, without forgetting the World Cup of 2014. 

- The expansion is occuring across the whole country, but perhaps a little more in Rio. I never saw so many connections from positive factors at the same time – affirms the president of the construction company Concal, José Conde Caldas.” – Source (more here, in PT)