The Aretine art historian and fabulist Giorgio Vasari tells a story in his “Life of Donatello” of a Genovese merchant who, with Cosimo de’ Medici as intermediary, commissioned from the sculptor a bronze bust. The transaction did not run smoothly. When the work was completed, the patron thought the asking price too high. “So the deal was referred to Cosimo, who had the bust carried to a courtyard above his palace and had it placed between the battlements overlooking the street so that it could be better seen.” Up in this arena of heightened visibility, the artist and patron both proved intransigent. Cosimo told the merchant that the price stated by Donatello was actually too low; the purchaser, however, calculated that the price meant the artist was earning more than half a florin a day, and that this was too steep a price. Such accounting did not go down well with the artist