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Team

Jake Thomas has a unique background which combines advanced studies in Physics and WSET Level 3 certifications in Wine & Spirits. He has taught physics classes at Stanford and created more than 500 custom cocktails at high end resorts in the Bay Area. Whether he finds himself behind a desk, in front of a classroom, or working the bar, Jake is motivated by the impact he is able to have on others. Jake is a life-long learner who looks for new ways to stretch beyond his comfort zone. We are grateful to have access to his curiosity, knowledge, and mixology magic as a member of the firm’s administrative team. When he has time outside of work and is not busy researching Quantum Field Theory, Quantum Electrodynamics, Chaos Theory or mixing whiskey cocktails, Jake is fond of trips to Canada for back country snowboarding.

Jake ThomasIrrational Number Nerd

A graduate of North Dakota State University, Summer majored in accounting and minored in fraud investigation, finding her way to the field of accounting almost by accident. Initially planning a career in law enforcement, everything changed when she took her first accounting class and discovered a new passion. Specializing in Individual and Business Tax, Summer is committed to finding tailored solutions for her clients through thoughtful communication. She firmly believes that a one-size-fits-all approach doesn’t work and takes pride in building strong client relationships to address unique needs. Outside of work, Summer is an avid traveler and finds joy in exploring new places and cultures. A proud animé enthusiast, she admires the profound teachings and life lessons delivered by its characters. Her hobbies also include Pokémon, reading (especially Stephen King novels), and spending time with her growing family. Summer cherishes the years she spent living in the beautiful country of Bahrain, which enriched her love for different cultures and experiences. Summer is a CPA licensed by the Montana Board of Public Accountants.

Summer ZitoAnimated Taxster

Aaron Soon, an alumnus of the Shidler School of Business at the University of Hawaii at Manoa, brings a unique blend of experience to our tax team. Originally embarking on an engineering journey at UCLA, Aaron eventually returned to his Hawaiian roots, where he pivoted to a focus in accounting and finance. His diverse academic background and prior work experience enriches our team with fresh perspectives. Aaron's successful journey to passing the CPA examination was partly fueled by collaborative study sessions with his wife, who was concurrently preparing for her medical boards. In his role as a dedicated tax professional, Aaron draws inspiration from his wife's resilience and determination. The couple cherishes their moments together, finding solace and strength in each other's company amidst their demanding careers. A versatile athlete, Aaron has dabbled in various team sports, ultimately finding his passion in cross country and track during his high school years. These days, away from the spreadsheets and tax forms, Aaron is often spotted at HiClimb, honing his bouldering skills and embracing the challenges of climbing, much like he tackles complexities in taxation. Aaron is a CPA, Certified by the Hawaii Board of Public Accounting

Aaron SoonTax Crux Crusher

Erica Umphreyville has always been surrounded by numbers and accountants—from her parents to her siblings—but her true passion lies in making a meaningful impact on her community and for her clients. A graduate of Southern Methodist University in Dallas, Texas, Erica holds a Master of Science in Accounting. She honed her expertise at a Big 4 CPA firm, focusing on the governmental and non-profit sectors, and more recently served as a Controller, overseeing the financial operations of 24 Title I charter schools. Erica’s deep connection to her work is inspired by the powerful women in her life, especially her mother, who rose from an Accounts Payable Manager to a Director of Finance in the Biotech industry, embodying the hard work and dedication that Erica values. Though based in Texas, Erica is excited to work with wineries, leveraging her unique blend of analytical prowess and creative problem-solving to unravel complex accounting challenges and help clients achieve their goals. When she’s not delving into data or strategizing with clients, you might find Erica appreciating nature, whether it’s walking on a trail near her apartment or engaging in a competitive game of pickleball. She also enjoys exploring her culinary side, cooking Italian food, and growing her own herb and vegetable garden. Erica is a CPA, licensed by the Texas State Board of Public Accountancy

Erica UmphreyvilleAltruistic Auditor

Guy Carl has been a CPA with BDCo since 1992 and a partner since 2005. He specializes in helping small wineries with tax preparation and planning, financial statements, forecasting, and accounting software guidance. Guy enjoys helping business owners understand how their businesses work and perform, and empowering them to be more successful. Born and raised in the Napa Valley, Guy holds an accounting degree from St. Mary's College. He is a past-active member of the Napa Active 20-30 Club, an organization dedicated to helping children in the community. An avid outdoorsman, Guy can often be found alongside a mountain stream or floating on a lake with a fishing pole nearby. Guy is a CPA licensed by the California Board of Accountancy.

Guy CarlProfit Prophet, CFO

Randy Gnagy has been a CPA for more than 35 years, having first joined BDCo in 2000. He is the firm's senior tax specialist, and has a great deal of experience in interstate taxation and tax preparation for nonprofit organizations. Over the years he has been active in Junior Achievement, the Arts Council of Napa Valley, the Napa Valley Shakespeare Festival, and has served on the board of Napa Emergency Women's Services and UpValley Family Centers of Napa County. He has also done volunteer work at local schools. An avid cyclist, he holds a BA in history from California State University, Fresno. Randy is a CPA licensed by the California Board of Accountancy.

Randy GnagyPain Reliever

Craig Underhill is the firm's CEO. He has been a CPA for over 37 years and has been with BDCo since 1995. Leveraging his vast accounting and management expertise, he's adept at steering wine and hospitality entities towards strategic success. His education in strategic management, productivity, and human behavior empowers individuals across all levels—from top executives to hourly staff—to reach their peak. A master at inciting introspective questions, Craig enables individuals to unlock their potential and bolster performance. He is the board chair for Junior Achievement in Napa County and has led JA's expansion from 250 participants to over 4,000 annually. He holds a business administration degree from California State University, Chico and is certified in Strategic Performance Management. He is an active volunteer and trained handler for Aaron the Comfort Dog, a Napa celebrity. You can read Craig's blog posts here and hear him describe his vision for the firm here. Craig is a CPA licensed by the California Board of Accountancy.

Craig UnderhillEmperor of Enlightenment, CEO

Heather Sprauve is a native of Deer Park, California. She attended Pacific Union College (PUC) in Angwin, then transferred to their sister college, Atlantic Union College in South Lancaster, Massachusetts, before returning to Angwin to complete her degree. She started out as an art major but after taking her first business class, discovered an aptitude for accounting and made that her major. Heather moved to the Virgin Islands where she married and spent 18 years working for an accounting firm. She worked for BDCo part-time for a few years and then following the devastating impact of hurricanes Irma and Maria, returned to California. While she enjoys being back in California, Heather misses her daily view of the Caribbean Ocean from almost any spot on the 31 square mile island of St. Thomas. Her interests include hiking, traveling and exploring new places.

Heather SprauveGlobal Gallivanter

Diane Leenders is a graduate of Saint Mary's College in Moraga, California. She is an experienced tax professional who has previously held audit positions in both public accounting and industry. Diane is an open water swimmer who regularly competes, along with members of her family, in masters swimming events. She enjoys the feeling of gliding through the waves and the resulting sense of calm. Water is a recurring theme in her life, as she met her husband on a water skiing adventure. Diane is an early riser and her daily ritual begins with coffee and a view of the rising sun. Diane cherishes this time alone and feels that "each day provides an opportunity to make that day meaningful." Diane is a CPA, licensed by the California Board of Accountancy.

Diane LeendersIlluminator

Erica Riddle, CPA is a partner in Brotemarkle Davis & Co. specializing in tax and assurance services, operational reviews and business consulting. Erica also serves as the firm's wine industry analyst, spearheading the firm's efforts to provide and share key insights into the wine business with our customers. Erica joined BDCo in 2013 and has both a Masters in Accounting from California State University, Sacramento and a Masters of Science in Taxation from Golden Gate University. She is also certified in Strategic Performance Management. Prior to joining BDCo, she was the Labor Optimization Manager at Six Flags Discovery Kingdom. Although her office was located right next to a roller coaster, Erica says her favorite attraction at the park was the tigers she first got to know as cubs. As a knitting hobbyist, Erica says the key to her success is patience and concentration, which also makes her a wizard at spreadsheets, programming, and all things accounting. She also holds the unprecedented distinction of being a candy maker and is a "third-generation Riddle Brittler". Erica is a CPA licensed by the California Board of Accountancy.

Erica RiddleExcelerator

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1000 Main Street, Suite 250
Napa, CA 94559

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707-963-4466

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FAX  :  707-266-1673
email  :  info@bdcocpa.com

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