General Manager of the Hotel Vier Jahreszeiten in Hamburg (1975-1993) In 1993, after 18 years as general manager, Prantner left the Vier Jahreszeiten. In his time at the hotel, he had tripled turnover, installed modern management systems with budgeting and marketing and taken the hotel to the top of the European hospitality league. Today he is the managing owner of RIMC - International Hotel Resort Management and Consulting GmbH.