He has been consulting for companies and organizations such as Dreamscape (USA), Beletrina (Slovenia), Arabic Language Center (Abu Dhabi), Podiprint (Spain) and Meta Solutions (Brazil). In the past I have consulted for Bonnier Books New Markets (Germany), HarperCollins (USA), Livres Canada Books, Elisa (Finland), Bookwire (Germany), Porto Editora (Portugal), Bajalibros (Argentina), and various Brazilian companies and entities such as Somos Educação and the Brazilian National Library. I have also co-authored several publishing studies and reports, particularly with Austrian consultant Rüdiger Wischenbart.
He founded the online book trade media PublishNews in Brazil and Spain and sold his equity in these companies in November, 2021. Carrehno has a degree in Economics and in Publishing at the Radcliffe Publishing Course, a summer programme that used to be offered by the Radcliffe College in Cambridge, US.