Ronald Leitner

On June 1, 2021, the property management company COLLIERS Immobilienverwaltung GmbH - as a subsidiary of COLLIERS INTERNATIONAL Immobilienmakler GmbH - was founded with Philip Engel as the managing partner and managing director under trade law.

Before that, after completing his law studies and the legal clerkship, he worked for 11 years, initially as the sole disciplinary and professional head and from 2016 as sole managing director of the property management company Prof Dr Thomas Keppert Immobilientreuhand GmbH.

Jan Gallner joined COLLIERS Immobilienverwaltung GmbH in June 2021 as Property Manager. At the beginning of 2019, he started his training as Real Estate Merchant at Prof Dr Thomas Keppert ITH GmbH and successfully completed it after joining to COLLIERS in march 2022.

Nicole Zimmel has been supporting Philip Engel, Managing Partner of COLLIERS Immobilienverwaltung GmbH, as Executive Assistant since July 2021. Prior to that, they had been working together at Prof Dr Thomas Keppert Immobilientreuhand GmbH. As of March 2022, Nicole has also taken on the role of Administration Manager.

From May 2019 to November 2020, she was assistant to Managing Director Thomas Belina and CEO Georg Muzicant at COLLIERS International Immobilienmakler GmbH. In addition, she handled the daily office operations. Prior to joining Colliers, she held assistant positions in a wide variety of industries: film and media, IT, energy, as well as agriculture and research. Her educational training had an equal focus on economics, communications and languages. Nicole completed her master's degree in Media Management from the University of Applied Sciences St. Poelten in 2010.

Medina Brao has been supporting COLLIERS Immobilienverwaltung GmbH as a Property Manager in training since April 2022. She attends the vocational school for office clerks with a focus on real estate management. 

Camilla Ruff joined the COLLIERS Immobilienverwaltung GmbH in May 2022 as Accountant. Before that, she was working as Customer Advisor in an Austrian bank for 11 years. Camilla also has several years of working experience as a flight attendant.

Originally coming from new construction and project development, Rainer Marschall moved into asset management via various positions. In his previous positions, he was responsible for a wide range of properties. In doing so, he managed properties ranging from apartment buildings to large-volume portfolio properties in the office, commercial, residential and special real estate sectors.