Maner Costerisan, a full-service public accounting, technology, wealth management, and business consulting firm in Lansing, announced five team members have been promoted to principal and Katie Hamilton has been appointed to the board of directors effective Jan. 1.
Hamilton, a principal at the firm, oversees Maner’s tax department and is responsible for the firm’s tax growth strategy and client service. Additionally, she provides expert counsel on income, estate, and gift tax planning for the firm’s wealth management clients.
Hamilton joined Maner in 2019 and, one year later helped launch Maner Wealth, the firm’s wealth management service, which was recognized in 2023 by Accounting Today as a top firm nationally based on assets under management. She was also named a 10 Over the Next Ten Award recipient in 2019 by the Lansing Regional Chamber of Commerce, which recognizes the top young professionals in the region.
“Katie is tireless in finding ways to support our clients and provide solutions tailored to their unique needs,” says Trey Williams, president of Maner Costerisan. “She’s been essential to the growth and development of our wealth management practice. “Katie is smart, humble, and committed to making our firm a great place to work for those in the tax department and others across the firm.”
Additionally, Jessica Fleet, Joel Korson, Nick Kossaras, Stephanie Kossaras, and Clayton Stiffler have been promoted to principal. These moves reflect their professional expertise, leadership qualities, and the confidence earned by the firm and its clients.
Fleet joined Maner Costerisan in 2014 and works in the firm’s accounting and outsourced solutions department, where she provides services to clients across various industries, including healthcare and small and midsize businesses. Fleet graduated from Saginaw Valley State University with a bachelor’s degree in professional accounting.
Korson provides accounting, audit, tax, and consulting services to small and midsize business clients, particularly in the construction and manufacturing sectors. Korson started at the firm as an intern in 2013. He received a bachelor’s and master’s degree in accounting from Michigan State University in East Lansing.
Nick Kossaras joined the firm a decade ago after receiving his bachelor’s and master’s degrees in accounting from Michigan State University. He currently works in Maner’s audit department and specializes in providing audit services to Maner’s affordable housing and education clients. He is involved with the audit department’s strategic planning and is researching next-generation audit software to lead Maner into the future.
Stephanie Kossaras specializes in affordable housing and multi-state entities and provides tax advice, planning, and preparation to the firm’s for-profit clients. She works in Maner’s tax department and helps clients in the affordable housing sector, earning her Housing Credit Certified Professional (HCCP) designation. Kossaras also supports the firm’s employee benefi
