Background Paragraph: Artworks are sold at affordable prices [6] ranging from £5 to £1500. For many of the works, the price goes up as the edition sells out. The edition runs range from 30 to 10,000 editions. Each work comes with a digital certificate that is “signed, numbered and authenticated by the artist” [7][8] Once an edition is sold out, collectors can resell their works in the online marketplace. 
Story: Bill is an art aficionado. He is searching for some particular pieces to complete his collection. The Stillman edition he wants is still being sold on a normal marketplace, while the Grossman edition of pieces has sold out, and is only available  by private seller. 
Question: As more Grossman editions become available for sale will they become more or less expensive?
less.