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Senior management professional Stefan Erdtmann, founder of Oxygen2 Investments Germany, based in Berkeley, California, serves as the firm’s Managing Director in the company’s branch office in Krefeld, Germany. Fluent in English, German, and French and conversant in Spanish, he handles key accounts, marketing, market research, sales, and other daily operations. Stefan Erdtmann utilizes his expertise in managing multiple projects and finding creative solutions in bear markets at Oxygen2 Investments, whose team allocates and manages portfolios for international clients.Stefan Erdtmann began his career as an Audit Manager for Peat Marwick Mitchell LLC in Düsseldorf, Germany. In this role, he executed due diligence on company buyouts and conducted audits on German subsidiaries of U.S. and Japanese companies, as well as year-end audits. In addition to his current management duties at Oxygen2 Investments, Stefan Erdtmann also acts as CEO and owner of United Properties Immobilien & Anlagen GmbH in Krefeld, which he cofounded with his brother in 1995. The firm buys, repositions, and sells multifamily real estate. As such, he oversees a staff of 22 and a portfolio of hundreds of apartments.Skilled at multitasking, Stefan Erdtmann also serves as a Partner of Hausverwaltung Gebrüder Erdtmann in Krefeld, as General Manager of VIVUM Immobilien Treuhand & Verwaltungs-GmbH in Krefeld, and as CEO of AcasA Wohnwerte GmbH in Düsseldorf. A major shareholder in the latter firm, a real estate development business he joined in 1999, he oversaw project volume of $40 million in the first 3 years, with nearly 70 single-family homes currently under construction.At Westfälische Wilhelms-Universität in Münster, Germany, Stefan Erdtmann studied marketing and sales, as well as finance and taxes, graduating with distinction. He completed a Ph.D. in Marketing and Sales at Bergische Universität Wuppertal in Germany and lectured on international marketing. A certified public accountant, Stefan Erdtmann also maintains certification as a real estate appraiser.

Work experience



Bergische Universität Wuppertal


Westfälische Wilhelms-Universität