Balneário Camboriú, Brazil

With a population of just 40,308, this coastal Brazilian city swells to over 1 million during the summer tourist season, straining its infrastructure to the breaking point. The high-rise real estate market is dominated by local developers, with beachfront units fetching up to $10,000 per square meter - though the average is a still-lofty $3,000. Loose urban planning has allowed the construction of some of the tallest buildings in the southern hemisphere, but this density comes at a cost, as the influx of tourists regularly causes water quality issues and fresh water shortages. Access is limited to a single state highway, leading to chronic traffic jams. For those seeking a glitzy, Brazilian version of Dubai, Balneário Camboriú may fit the bill - but the relentless bureaucracy and fickle climate make it a poor choice for permanent living.