Skip To Content

    Administrative Staff

    Stephen Berezin

    Director of Operations

    C): 815-557-6697


    Stephen joined The Mattz Group in early 2019 as our Director of Operations.

    Born and raised in the South Suburbs of Chicago, Stephen attended Homewood Flossmoor High School and then Received a Degree in Latin American History and a Minor in Spanish from Tulane University in New Orleans. While at Tulane he had the good fortune to do an internship for the City of New Orleans’ Department of International Trade.

    Post College, Stephen joined the family supermarket business in South Chicago started by his grandfather and succeeded by his father. He flourished as a leader and increased sales and profits to a point that the family was approached by a major chain who bought the store.

    Stephen’s past has had a huge impact on his customer service, marketing, and sales skills. As a new Realtor in 2002, he used his professional background along with hiring the top Real Estate company in the country to ensure his success in helping his Real Estate Clientele.

    Stephen joined Keller Williams Preferred Realty in 2009 as a residential and commercial broker.

    In 2014, he accepted the position of Productivity Coach. He quickly grew the program from 25 agents to well over 100, helping KW associates with their skills, models, and businesses.


    John Tomasula

    Contract Negotiator

    O): 708-249-3140


    John Tomasula grew up in the Northwest Suburbs of Chicago. A former youth minister, he has filled several roles within real estate- as an independent agent, Open House Coordinator, Buyer Specialist, Executive Assistant, and his current role as Contract Negotiator.  He has been with the Mattz Group since 2015.  John is an avid Bears, Bulls and White Sox fan, and enjoys spending his weekends with his three nephews.  John’s focus is ensuring the team deliver’s the best quality service and strives to secure the highest value price the market will bear for our seller clients.


    Angela Hall Williams

    Client Care Specialist | Transaction Manager

    O): 708-249-3161


    Angela joined The Mattz Group in early 2019 as our Client Care Specialist and Transaction Manager.  She is focused on providing outstanding customer service to both our seller and buyer clients while guiding them through their real estate transaction.

    Prior to joining the team, Angela worked as a Staff Attorney and real estate broker with a focus on residential real estate transactions.She has served as Litigation Counsel at the Attorney Registration & Disciplinary Commission as well as a Cook County Public Guardian.