Zhen brings much experience to the firm with a strong background in corporate finance. He graduated from the University of Maryland in 1999 and has worked over the years for GE, Fannie Mae, TerraForm Power, TerraForm Global, and AmTrak in various senior finance positions including audits, mergers & acquisitions, and forecasting. He became a licensed insurance agent in 2023 for Messina Insurance Group, and became a managing partner of Mercer, Flangan & Company in November 2024. Zhen and his wife Ani live in Potomac, MD with their two sons.

As an experienced CPA with 28 years of experience, Roy has a proven track record of providing exceptional tax and business consulting services to clients. His expertise includes financial reporting, tax planning and compliance, audit and assurance, and business advisory services. Roy received a B.S. in Accounting at the Roberth H. Smith School of Business at the University of Maryland in College Park in 1997. His experience began as an auditor with CliftonLarsonAllen and then as a Senior Accountant with American Express Tax and Business Services, now RSM.  He has served as a controller and CFO for various companies in multiple industries.  Roy and his wife Mishelle live in Olney, MD with their three children, Giovanna, Luca, and Simona.

Steve is a licensed CPA and has been a tax professional for 50+ years; he has been with our firm since 2016.  Steve is a life-long resident of Frederick County - he  graduated from Frederick High School in 1968 and attended Frederick Community College, where he received his A.A. in Accounting, then moved on to Mount Saint Mary’s College for his B.S. in Accounting.  He served in the U.S. Army from 1968 – 1971.  He and his wife Paula have been married for 53 years; they live in Middletown, MD.  They have three children and three grandchildren.  They are active members of Faith Presbyterian Church.

Jo Ann started working at Mercer, Eubank and Company in 1985. Although the company has changed its name a few times over the years, she has worked here for 40 tax seasons. Before that, Jo Ann worked for two years at Sturgill, Reagan and Lehman in Westminster. She received her bachelor’s degree in accounting at Messiah College in December of 1983 and obtained her CPA license in 1985.Jo Ann grew up in Frederick only a few miles from our office. She graduated from Heritage Academy in Hagerstown.  Jo Ann volunteers for various organizations including the Carroll County 4–H & FFA Fair as treasurer of the livestock sale, New Windsor Lions Club, Marine Corps League & Job’s Daughters. She also works at the Maryland State Fair where her husband Andy is the general manager.   Jo Ann and Andy have been married since 1987; they have two sons and four wonderful grandchildren.

Lorraine is a CPA with over 30 years’ experience in individual and business tax preparation.  A native of Pittsburgh, Lorraine is a magna cum laude graduate of Robert Morris University; she became a CPA in 2000.  She operated her own bookkeeping and tax preparation business in Pittsburgh before relocating to South Central PA, where she worked for public accounting firms and specialized in small business accounting and income tax preparation for individuals, LLC’s, partnerships, and corporations.  She also worked on non-profit and fiduciary returns.  Lorraine has since moved to Maryland and has specialized in estates, trusts, and high net worth individual tax preparation, but her love has always been small business and individual income tax returns.  She has been employed at Mercer, Flanagan & Company since 2025 and is one of their newest employees.  Here, she especially enjoys the client services and personal touch found only in a small, regional firm.  Lorraine is a widow with three daughters and eight grandchildren.  She resides in Laytonsville, MD.

Mark De Berardinis, a Staff Accountant at Mercer, Flanagan & Company since January 2024, holds a bachelor’s degree in accounting and over 8 years of experience with simple to complex individual tax returns and small businesses. Mark makes taxes feel less intimidating. His friendly approach delivers clear solutions, helping clients breeze through their finances with confidence and a smile.  Mark was raised in Frederick, MD and now lives in Thurmont.

Susan is the Office Manager at Mercer, Flangan & Company, and she is usually the first point of contact for clients. With exceptional organizational and communication skills, Susan has ensured every client interaction is a positive one since 2004, when she joined the firm. She manages the flow of the office, oversees administrative duties, and supports the team by coordinating scheduling and managing client intake. Susan’s dedication to client satisfaction and her commitment to fostering a collaborative work environment are invaluable to the firm. Susan lives in Derwood, MD with her husband Mike; she has one son and five grandchildren.