Like any massive overhaul, smart cities present many challenges, and especially to existing cities. TechCrunch explores the benefits of a smart city that was greenfielded in Songdo, South Korea, but with a whopping price tag of $35 billion.

Cities like New York City and San Francisco that are great candidates for smart city features, would stumble for years through legislation, let alone raising the funds for these initiatives. The federal government has earmarked $80 million to invest in smart city development, but it needs to be stretched over more than 70 cities, bringing each cities pay out to only $1.1 million. That's loose change compared to what a full-scale commitment would require.

There are other implications as well, from a social perspective, that need to be managed and have been experienced first hand in New York City projects.

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