Mehta started his career as a sales person in the Mumbai office of New India Assurance Company Limited (NIACL). During this time, he got interested in the stock market and after a few days, resigned and joined a brokerage firm. In the early 1980s, he moved to a lower level clerical job at the brokerage firm Harjivandas Nemidas Securities where he worked a jobber for the broker Prasann Pranjivandas Broker who he considered his "Guru".