GJM Advisory

Yesterday, a few of us took a break from spreadsheets and tax forms to gather at the Friendly Confines of Wrigley Field for a Cubs game.

Our offices will be closed on January 23 and January 24, but our team will be working remotely. The best way to reach us during this time is by email. We appreciate your understanding—and hope everyone stays warm over the next few days!

Tax season is here! If you are looking to work with us this tax season to file your individual tax return, here is a great resource to get started.

https://mailchi.mp/ffbc0bc2b392/a-simple-path-to-a-stress-free-tax-season

✨ Happy New Year from GJM Advisory! ✨

No matter what goals or changes 2026 brings, you don’t have to navigate them alone—we’re here to help guide the way. Here’s to a year of wise decisions, steady progress, and peace of mind. 🥂

From our team to yours, we wish you a Merry Christmas filled with joy, gratitude, and time well spent with the people you love. ❤️

Your business is growing. Are your books keeping up? If your business has outgrown DIY spreadsheets and sticky notes, it's time to call GJM Advisory. Your hard-earned growth deserves structure. We'll help you build it.

A Purdue University – Calumet graduate with a degree in Management and a concentration in Accounting, Susan began her career in 2001 and earned her CPA designation the following year. In 2016, she launched Lange Tax & Financial Services in Mokena, IL, serving individuals, families, businesses, and charitable organizations with thoughtful tax, financial, and estate planning.

In 2024, Susan joined forces with Adam, Matt, and the GJM Advisory team to expand her reach and continue helping clients make wise financial decisions that align with their goals and values.

Susan is also a RamseyTrusted Tax Pro serving the south Chicagoland and Kankakee areas — a recognition of her integrity, professionalism, and commitment to putting clients first.

Beyond her work, Susan invests her time in her community as a board member and treasurer for Camp Manitoqua in Frankfort, serves on her church’s finance team, and is an active member of the Illinois CPA Society.

After earning his Bachelor’s degree in Business Administration (Accounting concentration) from the State University of New York at Potsdam, Austin transitioned into public accounting in 2016 while completing his Master’s in Accounting the following year.

Today, he serves individuals, business owners, and families with thoughtful tax and advisory guidance — from growing small businesses to managing high-net-worth and trust & estate clients. His experience spans construction, real estate, professional services, and the medical field.

Outside of work, Austin stays active and grounded through fitness and sports — with a lifelong love for baseball, MMA, hockey, and soccer. He’s also involved with the State CPA Society, AGC, and the Childhood Cancer Society, investing his time where he can make a lasting impact.

If your books are behind, your decisions are too. Stop running your business with outdated numbers. Get your financials update to date and keep them there with our help.

Bookkeeping shouldn't break your brain - or your budget. GJM Advisory offers clear pricing, consistent service, and communication you can count on. Let's simplify your finances together.

After graduating from the University of Missouri with a BSBA in Accounting & Finance, he began his career at large accounting firms in St. Louis. In 2004, he partnered with David Johns to launch Geoffrey, Johns & Associates, serving individuals and closely held businesses for nearly two decades. With over 32 years of experience, Mark has guided clients across industries including manufacturing, medical, transportation, agriculture, and professional services.

In 2022, Mark and David merged their firm with Adam and Matt to form GJM Advisory, expanding their ability to serve clients with excellence.

Beyond work, Mark gives back through organizations such as Child Network and Habitat for Humanity.

After graduating from St. Louis University with a BSBA in Accounting and later an MBA, David gained experience at major accounting firms before co-founding Geoffrey, Johns & Associates in 2004. With more than 32 years in tax planning, he has guided individuals and closely held businesses across industries like real estate, construction, manufacturing, medical, and agriculture.

In 2022, David and Mark partnered with Adam and Matt to form GJM Advisory, bringing clients even more resources and expertise.

Outside of work, David is active in his community, serving organizations such as Habitat for Humanity, Presence St. Mary’s Hospital Foundation, Kiwanis Club, and the Economic Alliance of Kankakee County.