Potential buyers consider ‘St. Francis’ (center) by Kehinde Wiley, on view at Sotheby’s as part of ‘Shake it Up: Works from the Mario Testino Collection’ in 2017. Photo by Michael Bowles/Getty Images ...

The art business can be unpredictable, especially in New York. We asked several art dealers how they stay afloat — and how much it costs to do so. By Julia Halperin Without galleries — the point of ...