Archive for Executive Management

Diane Cullinan Oberhelman

Diane founded Cullinan Properties, Ltd. in 1988 after being in the real estate business since 1981. Her vision and commitment have led to successful Cullinan projects throughout the Midwest, Texas and Southeast.

Diane is nationally regarded as a visionary, a passionate business owner, and a leader in the real estate development industry. Today, Cullinan Properties has evolved into a premier provider of real estate development and acquisitions, focusing on commercial and mixed-use developments including retail, medical, office use, and multi-family nationwide. Cullinan Properties has owned and developed over $1 billion in projects and has had a strategy that has successfully executed and delivered in recent turbulent economic times.

Diane is married to Doug Oberhelman and has four grown children: Kathleen Cullinan Brill, Maureen Cullinan Bennett, Alison Cullinan Unkovich, and Allen Cullinan. Doug is the recently retired Chairman and CEO of Caterpillar Inc. He currently serves on many outside boards and is Chairman for DDI, an investment firm managed by Doug and Diane. They have 12 grandchildren.

Diane’s leadership and board affiliations are numerous and have included chairman of the Illinois Chamber of Commerce, Illinois Development Finance Authority, two-term member of the Federal Reserve Advisory Council of Chicago, Illinois Economic Development Board, Ducks Unlimited Board of Directors, Multi-Ad Services, Inc. Board of Directors, Peoria Civic Center Authority Board, Susan G. Komen Board of Directors, co-chair of the Salvation Army Tree of Lights Campaign, OSF Hospital Foundation Board of Directors and board member and co-founder of Kids Konnected.

Her awards and recognitions include being inducted into the Illinois Conservation Foundation’s Hall of Fame (2021); receiving the Robert H. Michel Lifetime Achievement Award for Distinguished Community Service (2020); receiving the Illinois Chamber of Commerce Athena Award (1996); honored as a 40 Leaders Under Forty Alumnus of the Year (2015); induction into Junior Achievement’s Central Illinois Business Hall of Fame (2006); Boy Scout Distinguished Citizen of the Year Award for Central Illinois (2005); Central Illinois Volunteer of the Year Award (2005); and being named one of 25 Women In Leadership (2002).

Christopher M. West

Chris leads the Cullinan Properties organization with specific responsibility for implementation of new developments, leasing, marketing and administration. With more than 35 years of experience, he has successfully completed the development and re-development of hundreds of millions of dollars in mixed-use, retail, office, medical and multi-family projects, including the master planning and development of projects such as Streets of St Charles, The Levee District and Grand Prairie Developments. Chris pays particular attention not only to the flow and logistics of a development, but also to the special amenities which can set a project apart from its competitors.

Prior to joining Cullinan Properties in 2002, Chris served as Vice President of Development with Urban Retail Properties Co., where he was responsible for developing, expanding and renovating more than ten major projects nationwide. Preceding Urban Retail Properties Co., Chris had various roles in Property Management for JMB Properties. He holds a Bachelor of Science Degree from Illinois State University.

Chris is a member of the International Council of Shopping Centers (ICSC). He is also a licensed real estate broker.

Michael C. Owens, C.P.A.

Mike leads Cullinan Properties’ investment activities and ensures the necessary capital stack is in place for all Cullinan projects from national, regional and local sources. During his time at Cullinan Properties, Mike has been the point person on over $1 billion of construction, mini-perm and permanent financing. He also leads Cullinan Properties’ Office and Medical Division. Currently, Cullinan Properties’ portfolio has in excess of $200 million of medical facilities. Including previous projects completed, Cullinan has developed over $300 million of office and medical projects in the last 10 years.

Prior to joining Cullinan Properties in 1995, Mike served as Senior Financial Analyst and Property Manager for Equitable Real Estate Investment Management (EREIM) in Chicago, a third party asset manager where Mike maintained an asset portfolio in excess of $300 million. Preceding Equitable, Mike was a Senior Property Manager for Equitable’s sister company, Compass Property Management. In 1988, Mike began his career as a Senior Auditor at Grant Thornton, a Chicago-based public accounting firm where he performed audits for a variety of client types including municipal, manufacturing, financial and real estate. Mike holds a Bachelor of Science Degree in Accountancy from University of Illinois and is a Certified Public Accountant (CPA).

Mike serves on the Board of Directors for the Streets of St. Charles Community Improvement District (CID).

Timothy J. Hogenkamp, C.P.A.

Timothy oversees the Accounting Department including all of its operations, treasury functions, company cash management and insurance risk management, as well as involvement with various tax and other finance matters. He also is responsible for driving strategies that grow Cullinan’s investor base.

Prior to joining Cullinan Properties, Timothy spent close to 18 years as Vice President at Staenberg Group and THF Realty, where he was responsible for all operating accounting, budgeting, tax compliance, financial reporting, lease administration, risk management and human resource functions.  He also has experience in startups, growth and billion-dollar industries having served in various capacities with Venture Stores, Anheuser-Busch and other organizations. Timothy holds a Bachelor of Science in Business Administration Degree in Accounting from the University of Missouri. He passed the CPA exam in 1993.

Timothy volunteers his time with St. Louis Crisis Nursery and has held board positions there for over 10 years. He is also involved with the Cystic Fibrosis Cycle for Life event and Gateway Off-Road Cyclists (GORC).

Sean R. Garrett

Sean leads Cullinan Properties’ Acquisitions and Dispositions Department with responsibilities for identifying acquisition targets, conducting financial analysis and due diligence, and ultimately closing on purchases. As a diversified real estate company, Cullinan’s acquisitions span several different asset types and range from raw development ground to stabilized, income-producing assets. Aside from acquisitions, Sean also heads up key strategic dispositions to ensure the Cullinan portfolio is well-balanced and consists of assets that align with our long-term portfolio strategy.

Sean provides daily direction to the leasing, marketing, and construction departments to help guide potential opportunities from inception to reality. He is responsible for maintaining and establishing many key relationships at Cullinan whether they are municipal partners, equity investors, brokers, buyers, sellers, or tenants. Helping our clients achieve success is a guiding value of our company and provides Sean with daily motivation.

Prior to joining Cullinan Properties in 2011, Sean served as a Development Associate in Washington, D.C. at Western Development Corporation, where he coordinated the pre-development of over 1 million SF of retail and mixed-use projects. He was also a contributing team member during the founding of, which is now one of the leading real estate crowdfunding platforms in the country. Sean graduated from the University of Pennsylvania.

Sean is actively involved in the Peoria community. He currently serves on the Peoria CEO Council and as a Board Member of the BizPAC of Central Illinois where he recently completed two terms as Chairman. Sean has sat on the Advisory Council for the Emerging Philanthropists and has served on several cabinets and committees for the Heart of Illinois United Way.

Sean and his wife Crystal love traveling, mountain biking, and snowboarding in their free time. He is a native of Albuquerque, New Mexico and has grown up in the real estate business as the son of a real estate developer.

Steven C. Gatton

Steven oversees all aspects of property operations, including supervision of both in-house personnel and third party firms. He coordinates leasing and tenant coordination related activities for the managed properties, and oversees Cullinan Properties’ Information Technology.

Prior to joining Cullinan Properties in 2017, Steven served as Finance and Asset Manager for The Staenberg Group, where he led the company on various financial strategies and debt placement for all new and existing projects. His responsibilities also included day-to-day operations and management of all TSG Retail Properties in the Midwest and Eastern United States. Preceding The Staenberg Group, Steven worked for THF Realty, where he managed 17 shopping centers totaling over 3.3 million square feet. He also served as a Senior Financial Analyst at THF Realty and was involved with placing $500 million of structured financing. Steven holds a Master’s Degree in Business Administration and Graduate Certificate in Entrepreneurship from Keller Graduate School. He also holds a degree in Business Finance from Lindenwood University.

Steven serves as President of Peoria’s Building Owners and Managers Association (BOMA) Chapter. He also serves on the board for Neighborhood House and is a board member for Mustaches for Kids Peoria, an organization that raises money for children’s charities in Peoria by encouraging men to grow a mustache in April. Steven was also selected to be a part of Senator Chuck Weaver’s 1,000 Pounds Project, an initiative focused on impacting the greatest needs of the Peoria community. He is a graduate of Peoria Area Chamber of Commerce’s 43rd Annual Community Leadership School and currently serves on the Community Leadership’s Planning Committee.  Steven is active in youth sports where he is currently a coach for Peoria FC United and also coaches in Dunlap’s recreational youth baseball sports organization.

Kathleen Brill

Kathleen oversees the Leasing Department and is responsible for new development and existing property leasing and sales at properties owned and/or managed by Cullinan Properties. She has successfully completed over 1,000,000 square feet of transactions with Cullinan Properties, including big box and junior anchor retailers such as Target, Costco, Gordmans and Hy-Vee, as well as numerous national and regional small shop tenants and restaurants.

Prior to joining Cullinan Properties in 2006, Kathleen served as a Broker with InCommercial Property Group. She holds a Bachelor of Arts Degree in Business from the University of Wisconsin-Madison.

Kathleen is a member of the International Council of Shopping Centers (ICSC). She co-founded the Peoria area Kids Konnected, a support group for children of parents with cancer. From 2008-2013, Kathleen served as Auxiliary Board President for the Sue Duncan Children’s Center, a safe haven for children to strengthen core academic skills while also developing self-esteem, respect for others and a renewed sense of hope. She continues her affiliation with the organization as a board member. Additionally, Kathleen served on the Auxiliary Board of the Art Institute of Chicago. She has been recognized by Real Estate Forum as one of the real estate industry’s Leaders Under 40.

A. Michael “A.T.” Toroyan

A.T. leads the leasing and sales-related functions of Cullinan’s multi-asset class real estate portfolio, overseeing the negotiation of all leases, purchase and sale agreements, lease renewals and lease terminations. A.T. works with the Construction, Property Management and Finance Departments throughout the entire process, from LOI through Lease/PSA execution.

With over 30 years in the commercial real estate industry, A.T. brings a broad background in various aspects of commercial real estate, including leasing, acquisition, design, construction, development and legal in a wide range of asset classes. Throughout his career, A.T. has held both equity and management positions in restaurant, retail and service sectors as a franchisee and a franchisor. While most recently at StreetView LLC, a boutique real estate and consulting firm, A.T. was active in restaurant site selection and consulting along with office, industrial and multifamily. In his prior positions, including VP of Leasing and Director of Legal for south Florida based Retail Property Group, A.T. has assisted more than 100 national public and private companies culminating in a multitude of transactions.

A.T. is an alum of Michigan State University, where he received his Bachelor of Arts Degree in Business Management. A.T. went on to earn his Juris Doctorate Degree, with an emphasis on business, real property and construction law, from University of Detroit School of Law.  A.T. is a volunteer with non-profit organizations Eat Better Live Better, Friends of Drew Hafets and No Kid Hungry.