Sara Henneberry, Mark’s sister, joined the Abacus Builders team in 2023 and now serves as the company’s Head Bookkeeper. A qualified CPA accountant with specialized training in forensic accounting, Sara brings a wealth of expertise to her role. Before joining Abacus Builders, she spent two decades managing financial operations at Abbott Pharmaceuticals, where she gained extensive experience in financial management, compliance, and strategic budgeting.



Sara’s decision to immigrate to the USA with her family was driven by her desire to contribute to the growth of Abacus Builders and be part of the family business. At Abacus, Sara is responsible for managing the accounting needs of both the core company and its LLC sister companies, especially those involved in Ground-Up New Construction projects.



Her key responsibilites include:



• Overseeing the general ledger and ensuring all financial transactions are accurately recorded.

• Managing the accounts payable and receivable process to maintain smooth financial operations.

• Tracking job costs and project budgets to ensure financial accuracy for every build.

• Preparing and maintaining updated tax reports, balance sheets, and annual budgets.

• Producing detailed financial statements to aid in strategic decision-making and ensure compliance.

• Monitoring and analyzing project financial performance to identify efficiencies and improve profitability.




Sara’s meticulous approach and deep financial expertise play a critical role in the continued success of Abacus Builders. Her contributions ensure that the company operates with financial transparency and precision, enabling the team to focus on delivering exceptional results to clients.



As both a trusted family member and a highly skilled professional, Sara exemplifies the commitment to quality and attention to detail that define Abacus Builders as one of Boston’s best contractors.