Click on one of the people below to find out more information.

  • Mike Manthei
    General Sales Manager

  • John Konstan
    Mercedes Brand Specialist

  • Cassandra Castro
    Mercedes-Benz Brand Specialist

             I have been in the luxury car business for about 2 years and just recently started in sales with prior background in finance. I enjoy spending time with my kids, the outdoors, sports, and shopping. I love helping people and look forward to helping you get into your new Mercedes-Benz!

  • Hunter Rohs
    Mercedes-Benz Concierge
    414-543-3000 Extension 245

    As the Mercedes-Benz Concierge, I take pride in learning all the technology in the ever expanding Mercedes-Benz product lineup. I hope to offer my knowledge to every Mercedes-Benz owner. Additionally, it is my goal to offer outstanding customer service and help every customer with any problem they may encounter, technology related and not.

    Outside of work, I can be found at one of southeastern Wisconsin's many lakes either fishing or water-skiing. During Wisconsin's long winter months I frequent the many ski hills in Wisconsin and other westward states. When the ever changing Wisconsin weather does not allow for outside activities, I spend my time tinkering with engines of all shapes and sizes. 

  • Ron Rafalski
    Mercedes-Benz Brand Specialist
    Ext. 120

    I have been selling high-line European automobiles since 1976 with leasing as a specialty.

    My hobby is collecting miniature art.

    I am an avid runner that belongs to The Badgerland Strides Running Club, and I participate in races throughout the year.

    I also enjoy sailing.  I was a member of the Milwaukee Community sailing center for years and owned my own boat.

    When I have free time, you will find me in Door County.

    Monday:  9-5
    Tuesday:  9-8
    Wednesday:  OFF
    Thursday:  9-8
    Friday:  9-5
    Saturday:  9-5

  • John Callen
    Service Dispatcher
    Ext. 131

    Monday:  7:30-5:30
    Tuesday:  7:30-5:30
    Wednesday:  7:30-5:30
    Thursday:  7:30-5:30
    Friday:  7:30-5:30
    Saturday:  OFF


  • Debra Kegel
    Business Development Coordinator
    Ext. 216

        I have been with the International Autos for 2 years in the Business Development Center.  I've worked in the car business for a total of 4 years.  I love spending time with my family and my interests are crafting, camping, gardening and decorating.  

  • Dennis Spingola
    Parts Manager
    Ext. 127

        With many years in the automotive industry, I bring a level of experience and professionalism that has set the bar in his Department.  I am the Parts Manager at International Autos and work to set an example for my staff through positive motivation.  Second-generation Spingolas can be found working for the IA Group as well.

        During my spare time, I can be found at home with my wife and dogs.  Together, we enjoy riding our Harley Davidson motorcycles.  I am an avid outdoorsman who enjoys snowmobiling in the winter and boating during the warmer months.

        Whether ordering an oil filter for someone who likes to work on their own car, helping a Technician in the shop, or suggesting the perfect gift from our boutique, I am here to help!

    Monday:  7:30-5:30
    Tuesday:  7:30-5:30
    Wednesday:  7:30-5:30
    Thursday:  7:30-5:30
    Friday:  7:30-5:30
    Saturday:  OFF