In 2007 Koos started as an office manager at Grey Men to gain experience with the financial assistance of artists. Within a short time Koos builded artiest roster with his main focus being Dutch hip hop clients.
In 2013 Koos started his own management firm called Bespoke. Bespoke provides business management for The Opposites, The Partysquad, Great Minds, Adje, Jiggy Dje and others.
He was active as a juror for the Grote Prijs of the Netherlands. Koos is also the owner and booker of Appelsap Festival and he is in the commission of the Edisons.