Broker Check

Our History & People

Our History

Mainsail was established by Les Gosule, Bob Jesson and Jim Oslin in 1999 as a way to serve the growing financial planning needs of their CPA firm, Gosule, Butkus & Jesson, LLP in Milton, Massachusetts. Over the last 10 years Mainsail began building a relationship with David Alexander of Alexander Advisors in Harvard, Massachusetts through their wealth management study group and mutual partnership with 1st Global, a resource partner to the CPA-centric wealth management industry.

In 2017, the two financial planning firms became Mainsail Advisor Group, LLC. The firm’s ability to formally share expertise and coordinate services represents an evolution and growth in becoming a premier provider of tax-efficient wealth management services to eastern Massachusetts through the advancements in technology and resources provided through Avantax.

Our People

David Alexander* CPA/PFS, MST, CFP®

Financial Advisor


David is a Managing Partner at  Mainsail Advisor Group, LLC, and leads the firm’s office in Harvard, Massachusetts. David is also the founder of Alexander Advisors, an accounting and financial advisory firm providing tax, business consulting to a diverse group of clients for over 30 years.

David received his Bachelor of Science degree and Master of Science degree in taxation from Bentley College and became a CPA in 1986.

In addition to being a CPA, he is a Personal Financial Specialist (PFS) and CERTIFIED FINANCIAL PLANNER™ (CFP) professional. David is a General Securities Broker and Investment Advisor Representative with his Series 7, Series 66, and is licensed to offer various insurance solutions.

David is a member of the American Institute of Certified Public Accountants, Massachusetts Society of Certified Public Accountants and is active in several community events and boards.

Fadi Khoury* MBA, CRC

Financial Advisor



Fadi is a Managing Partner and Financial Advisor with Mainsail Advisor Group, LLC.

After more than fifteen years in corporate business management, Fadi decided to dedicate his planning and management skills to help individuals, families and small businesses.

His strong background of helping businesses has been a real asset to building individual relationships and developing a personal service approach. Fadi spends time understanding each client goal; bringing customized, out of the box solutions to help navigate through the uncertainties of the future with confidence and minimal risk.

Fadi cultivates a business practice that is goal driven, holistic and centered around clients needs and goals.

He has been in the financial industry and wealth management for over a decade. He is a CRC (Certified Retirement Counselor)  and  holds an MBA (Masters in Business Administration).  Fadi is fully licensed and registered for Securities and Insurance.  

Fadi is married, has three beautiful children, and enjoys volunteering with local communities.

Cindy Coupal

Wealth Management Coordinator


Cindy is a Wealth Management Coordinator at Mainsail Advisor Group, LLC.  She joined the firm in 2012, bringing over 30 years of business experience to the practice. On a day-to-day basis, Cindy focuses on client service.  Her responsibilities include guiding the wealth management operations including marketing, client services, establishing and maintaining client accounts and information systems, internal reporting, and is a liaison between Avantax and our clients.

Cindy holds a Bachelor of Science degree in Business Management from Fitchburg University. She is a lifelong resident of Massachusetts recently moved to Florida. She enjoys spending time with her family.

Robert M. Jesson, CPA, MST

Bob is a founding partner in the CPA firm Butkus & Jesson since 1983, and a consultant in Mainsail Advisor Group, LLC since 2001.

Since his career began, Bob has taken a personal interest in his clients. Additionally, he is an advocate for small and medium-sized businesses and is known for bringing a common sense approach to solving complex tax and operational problems.

Bob’s professional education is a testament to his work ethic and commitment to furthering his knowledge in business and taxation. He received his business administration degree in 1980 from Bentley College.

He then earned a Master of Science in taxation in 1985, and Advanced Professional Certification in taxation in 1990.

He earned both of these degrees while attending night school and working full-time in his chosen field.

Michael Sheridan

Financial Advisor



Michael is an investment Research and Analysis and a Financial Advisor at Mainsail Advisor Group, LLC.

Michael has over 20 years of experience in the small business and wealth management industry, with a background in investment research and financial planning. He works with the Mainsail team to provide tailored investment solutions and an exceptional client service experience.

Michael's extensive small business and investment background allows him to elevate client service to new heights. 

Michael received his degree in Economics from Brown University. He is a General Securities Agent and Investment Advisor Representative, holding the FINRA Series 7 and 66 registrations.

Outside of the financial world, Michael enjoys spending time with his wife and daugther.

Have a Question?

Thank you!