Our Team


CPA, Principal, Director, President

Employee Benefit Plans

Trey Williams, CPA, Principal, Director, President

Trey is the president of Maner Costerisan, guiding the firm’s strategy, overseeing daily operations, and working to grow the firm’s profitability and services.

In addition to his leadership roles, Trey provides services to businesses in the construction and service industries. He is an active and longtime member of Maner’s Construction team and assists with peer review services.

Since his career began, Trey has helped numerous clients overcome obstacles and address critical issues regarding their businesses. He shares his expertise with organizations outside of his clientele, presenting for the Michigan Association of Certified Public Accountants, Central Michigan Chapter of ABC and publishing articles for The Greater Lansing Business Monthly magazine.

Trey’s decision to pursue a career in accounting was the result of his being raised in a family-owned business, which helped him gain experience and shape his perspective on a number of business-related issues. His success today is a result of his overall enjoyment of the profession, including the people he works with and the clients he serves.

Trey resides in Grand Ledge, Michigan, with his wife Tamra. They have three children. In his free time, he enjoys spending time with his family, fishing, camping, playing golf and collecting coins. He is also an avid Michigan State University Spartans sports fan.

The most fulfilling part of my job is helping our clients and team members be the best they can. It’s rewarding to see their growth and development through the years and to have had a seat at the table.

Years of Experience



American Institute of Certified Public Accountants (AICPA)

Michigan Association of Certified Public Accountants (MICPA)

Construction Financial Managers Association (CFMA), Former Treasurer

Associated Builders and Contractors (ABC)

Associated General Contractors of America (AGC)

Old News Boys, Former President

Rotary Club of Lansing


Certified Public Accountant (CPA)

AICPA Advanced Defined Contribution Certification