Dennis has been a realtor since 1989. He started as a part time agent and eventually became full time in the mid 1990's He eventually started his own office with his wife Pamela in 2001 called DBP Realty. In 2017, he merged his company with Howard Hanna Holt and formed Howard Hanna Professionals.
Dennis is a member of the National Association of Realtors, on the Board of Directors of the New York State Association of Realtors and is vice president of Chautauqua Cattaraugus Board of Realtors.
Dennis has been involved in his community in many capacities. He has been a co chairman of St. John's Festa Italian for several years. Dennis is the past president of the Greater Olean Area Chamber of Commerce. He serves on Olean General Hospital Foundation Board and the Cattaraugus Region Community Foundation.
Dennis has been a youth coach for several of his children's sports teams in the past. He is a very active member of his church. Dennis has eight brothers and sisters all located in Western New York.