As we saw in parts 1 and 2 of this EC-1, by mid-2013, Nubank CEO David Velez had most of what he needed to get started. He’d brought on two co-founders, assembled ambitious engineering and operations teams, raised $2 million in seed funding from Sequoia and Kaszek, rented a tiny office in São Paulo, and was armed with a mission to deliver the kind of banking services that customers in a market as large and lucrative as Brazil’s should expect. Despite being named Nubank, however, the startup couldn’t actually be…