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Gus Patel, CPA, CA, EET, LPA

Gus’ background includes both engineering and accounting and provides him with a unique perspective for servicing clients in a variety of industry sectors. His experience in public accounting provides him with a broad spectrum of knowledge in both assurance and taxation.

Gus has extensive expertise in assisting clients with income tax accounting, owner remuneration strategies, business succession and estate planning, Canadian corporate and personal tax, indirect tax, voluntary disclosure application, net worth assessment and CRA tax audits.

Joe H. Cass, CPA, CA

Joseph Cass has extensive experience operating a sole proprietorship for very many years. Prior to opening his own practice, Joseph worked at several mid-size public accounting firms where he honed his expertise of corporate taxation, estate planning, and transactions advisory. Joseph serves as the lead engagement partner on Abacus’ largest clients and meritoriously holds a lifetime membership with the Chartered Professional Accountants of Canada.

Igor Kostioutchenko, CPA, CA, CD, CFE, CIA, LPA

Igor began his public accounting career articling for Deloitte LLP after graduating with distinction from the University of Toronto’s Rotman School of Management. There he obtained his Chartered Accountant, Certified Internal Auditor and Certified Fraud Examiner designations after completing rigorous training programs and accumulating requisite experience hours servicing a wide range of clients in a variety of advisory roles.

Igor has extensive knowledge of financial reporting and advisory through applying IFRS, ASPE and U.S. GAAP frameworks, conducting audits, reviews and compilations, advising businesses on restructuring, mergers, acquisitions and public market offerings, and conducting forensic investigations. 

Gevorg Chibukhchyan

Intermediate Associate

Gevorg specializes in the delivery of computerized bookkeeping services through integrating process automation and interfacing multiple technological tools into our clients’ accounting workflows. He works with clients, directly, to assist in the adoption of time-saving techniques, on-board cloud-based accounting packages, set up periodic reporting of financial information, and compile income and indirect tax information for regulatory compliance work.

Khrystyna Zhovnirchyk


Khrystyna began her career with Abacus Group shortly after successfully graduating from the Precarpathian National University with an Honours Masters of Accounting and Audit . She specializes in assurance-related activities, including: audits, reviews, and compilations, fulfillment of regulatory tax filings associated with those engagements, and assistance with various client transactions. Khrystyna is currently articling with Abacus as part of completing her professional licensing requirements with the Chartered Professional Accountants of Canada.

Other Associates and Practitioners

Including: George, Gary, and Barbara

We know the importance of the company that we keep. In order to be well-positioned to provide timely and cutting-edge services to our clients, we surround ourselves with associates and practitioners with a large array of specializations and abilities. Our business model enables us to build professional relationships with other firms, sole practitioners, experts, and the like. Our employees, partners, and network collaborate to ensure that our clients’ objectives always come first.