Indonesian online sales have received remarkable growth with as high as 20% consistently every year. In 2016, there were estimated more than 180 million internet users and have reached 40% of 250 million total inhabitants. Based on the surveys, there are four most popular online vendors in Indonesia, such as: Lazada, Tokopedia, OnLine eXchange and Bukalapak, with strong customer bases. Due to its tremendous growth, however, there is still very few studies can be found to understand the characteristics of emarketplace in Indonesia. For this reason, the article examines those most popular online vendors in Jakarta area, where the most buyers tend to have more experiences in conducting online purchases. The article utilizes the revised TAM as a valuable method to assess the important factors of online purchases such as: buyer and satisfaction factors, that comprised of: buyer perceived risk, seller's expertise and reputation, and convenience of buying. The findings are aimed to address the important factors that can be used to increase buyer satisfaction. The outcomes of the study are expected to provide valuable guidance for all e-sellers and buyers to understand Indonesian e-marketplace.