Among the most prominent and fastest-growing markets on the Internet are online marketplaces. The leader and main exemplar of this type of market is eBay. In this paper, we provide a comprehensive examination of the salient website elements and strategies as success factor in online marketplaces. In this exploratory analysis, we report on the behavior of different types of sellers and their distinct approaches for achieving their desired goals. The conceptual framework for this examination is based on marketing mix theory and its synthesis with competitive heterogeneity theory, allowing us to formulate a success model for sellers operating in this market. The conceptual model is empirically tested by the random collection of over 2000 auction listings from eBay’s Motors Division spread over a period of six months. Our results bring to light the presence of different types of sellers in this market, and the differences in website designs and strategies they use for success in this market.