Our Team

Ivan J. Dvorak, P.E., President

Ivan Dvorak maintains an active role in and has unfettered passion for the real estate industry. Over his tenure, Ivan has been involved in thousands of projects across North America and brings this extensive knowledge and experience to TRES.

Ivan was President and Chief Executive Officer of Teng & Associates, Inc. for sixteen years prior to its merger with exp Global, Inc. in 2010 and maintained the role of Executive Vice President - United States Operations until his retirement in 2012.

Ivan earned an MS in Civil Engineering from University of Zilina, Czechoslovakia in 1966, and is a registered Professional Engineer in multiple states.

Ivan is a past Board Member of Labe Bank, Chicago; a Fellow with the American Society of Civil Engineers; a member of the Chicago Club and Economic Club of Chicago; served as the City of Lake Forest Mayor's Council on Capital Improvements and on the Illinois Governor's Advisory Forum on Matters of the State.

Sean McMahon, General Manager / Managing Broker

Sean McMahon has been responsible for development of over 1 million square feet of residential buildings and has consulted on millions of square feet of commercial projects throughout North America.

Sean’s 20 years of real estate experience includes planning, deal structuring, finance and construction of complex mixed-use projects with special emphasis on managing the development process, the design and construction, and the financial performance throughout all phases.

Sean’s real estate career includes past positions with exp Global, Inc, Teng & Associates, Inc., MB Real Estate, and others.

Sean is a licensed real estate managing broker who graduated from the University of Southern California with a Bachelor of Urban Planning and Development.

Mary Zappa, Property Manager – Sales & Leasing

Mary Zappa has an established 26 years of experience in the Chicagoland real estate industry.

Mary has established herself in the real estate industry with respect to Leasing, New Home Sales, Retail Sales and Residential development. Mary has been involved with sales and marketing with respect to leasing, selling, training and team management.

Well known developers whom she has had experience over the years include, Equity Properties, MCL Development, Brookfield Properties, Del Webb, Sundance Homes, Concord Homes and Lennar.

Mary’s accomplishments include the Order of Excellence Award 2003 and Executive Award 2005 presented by the Chicagoland Sales and Marketing council.

Mary is a GREEN designated Real Estate Broker and LEED Associate. Memberships include USGBC, IREM with ARM she graduated with an Associate’s Degree in Business from College of Dupage.

Scott Schwank, Lead Maintenance

Scott Schwank ensures the TRES facilities receives the highest level of service for which our customers and residents have become accustomed to. Scotts's 17 years in the construction industry has refined his attention to detail, work ethic, and customer service which has been praised by our residents and staff.

Scotts has been a member of Local 52 Pointers, Cleaners and Caulkers Union, holding Certifications in OSHA safety, scaffold erection and operations, and heavy equipment operation.

Scott served for the U.S. Arm Forces from 1987 – 1991.