"My go-to methods for identifying new markets are competition analysis and complementary product or service analysis. Because of the myriad market research data available for every industry, direct or indirect competition analysis makes it really easy to determine the market size and growth potential. Additionally, because most companies make their products and services accessible, one can purchase the competitor's product or get a free trial of a service. On the other hand, complementary products or services help widen the horizon for new markets. For example, if I'm looking to sell internet service in a new area, I would also look at the current offerings in TV services there. If I were selling furniture, I could look at sales data in real estate and property management, like vacancy and turnover rates."
