The Business Evaluation Services Leadership Team

Charles Stiles - CEO of Business Evaluation Services

Charles Stiles owned, managed, and grew numerous retail gourmet food and gift shops with world-class customer service. In 1996, his success led to the creation of one of the most respected and comprehensive mystery shopping and business evaluation companies in North America. In 2014, BES acquired two of the most notable brands in the industry (Customer 1st and BMA). They service a growing cadre of national and international clients, such as Disney, Microsoft, YMCA, and many more. As the host of Food Network’s Mystery Diners, he continues to elevate the customer service evaluation industry by bringing awareness to the importance of customer service to business success. Charles speaks nationally on customer service and culture building topics to leaders and the media. Charles has been an active member of the Mystery Shopper Providers Association (MSPA), since 2001. Over the years, he’s served on many MSPA committees, including Chair of the Public Relations Committee.


Carl Phillips - Founder of Customer 1st

Carl Phillips, founder and CEO of Customer 1st, is well known as one of the “fathers” of the mystery shopping industry and nationally as a speaker and trainer on a wide range of customer service and brand protection topics. He launched Customer 1st in 1996, after twenty-six years of successfully exceeding sales goals with his first-generation mystery shopping techniques as a manager of department stores across the country. Customer 1st grew into an international mystery shopping company with an impressive list of clients across every industry from retail clothing and restaurants to banking, auto-motive, and new home construction, such as Sketchers, Subway Marketing Group, and Calvin Klein Furniture. Carl is a charter member of the Mystery Shopper Providers Association (MSPA). He held MSPA Executive Board positions for seven years and spearheaded the development of professionalism standards for all mystery shoppers.


Peter Thorwarth - Founder of Best Market Audits (BMA)

Peter Thorwarth, founder of Best Market Audits (BMA) developed an early interest in customer service. At the age of ten, he pointed out while in a grocery store that automatic doors were only available for people entering, but not for those exiting. “The people leaving need automatic doors more, because their hands are full,” Peter told his father. His dedication to improving customer service to boost sales and customer retention led him to create BMA in 1991. For over twenty years, BMA has led the mystery shopping industry in delivering objective, detailed reports to clients with sophisticated but user-friendly online systems. BMA has consistently ranked as one of the best known mystery shopping service providers. The company regularly provides 1500+ mystery shops a month to national and international clients, from AT&T Wireless and Nielsen Research to Corning and JC Penney.


Nina Leyva - Operations Manager

Nina is the Operations Manager of Mystery Shopper Services. Nina has been a loyal team member since the year 2000. Initially, Nina began working for BES on a part-time basis in our call center. Because of her work ethic and ability to learn quickly, Nina became the full-time call center supervisor. Through the years Nina has worked her way up in key management positions in all departments of the company. In 2014 Nina was promoted to the operations manager for all three divisions of Business Evaluation Services. (MSS, BMA, and Customer 1st) In her role, Nina provides administrative support and supervision to the entire MSS team and has become an integral part of the company’s overall success. When not working, Nina enjoys spending time with her family, music, and traveling.


Theresa Wilson - Quality Control Department Team Supervisor

Theresa is currently the Quality Control Manager for all divisions of BES including MSS, BMA and Customer 1st. Theresa began working for BES in 2001 as a receptionist, and has worked her way up through all divisions of the company. Her love of reading, and her passion for accuracy led to her current position as the managing supervisor for the quality control division. Her job duties include overseeing her editing team and ensuring each mystery shop report that is received is thoroughly checked for accuracy, content, and grammar before being sent to the clients, as well as assisting other team leaders in other departments when needed.


Emma Valdivieso - A/R A/P Accounting Department Team Supervisor

Emma was born and raised on the beautiful coast of Central California. She studied at California Polytechnic State University in SLO where she received her BA in English and minored in Accounting. Her goal was to become a teacher but was quickly placed in a bookkeeping position where she found the culture of numbers much more fascinating. Emma came to BES in December of 2009 where she started out as scheduler and editor, working her way through the whole process of the mystery shopping business, to eventually become the Accounting Manager. In her free time Emma loves to help her community through several charities. She is the President of the Five Cities Dog Park Association, volunteers for a Feral Feline Program, is on the planning committee for the Annual Pismo Beach Turkey Trot whose proceeds fund the SLO County Food Bank, and finally is the CEO of SLO County Golden Retrievers, a non-profit 501c3. Much of her charity work is done with a very understanding husband and three Golden Retrievers in tow. When she has a moment to herself, she shares it with her horse.