Lili
Economic historians of art and other commodities spend years working out the modern equivalents for sale prices and artist compensation. There are many complex factors involved. You really need to look at books on the subject. John Michael Montias did much work on the art market in the Dutch Golden Age. See one of his books below. See also the book by Paul Crenshaw and perhaps also Simon Schama's "The Embarrassment of Riches: An Interpretation of Dutch Culture in the Golden Age." Another historian who has worked on economic issues (involving the Italian Baroque period) is Richard Spear.