The document discusses the cost factors involved in creating an e-commerce marketplace app, highlighting different types of marketplaces such as vertical, horizontal, and global. It details essential features for an effective marketplace application, including user registration, product listings, payment integration, and order tracking, while also outlining the various aspects influencing development costs like platform selection, design, functionality, and maintenance. The estimated development costs range from $7,000 to $70,000, depending on the complexity and features of the app.