Online marketplace for real estate transactions

Under an embodiment of the invention, a web site system maintains a real estate web page. The web page has an aerial image map of a geographic region that can be navigated by a user. The web site system facilitates online collaboration for real estate transactions. When the user registers, the system creates a user account for real estate information. Real estate agents and/or other real estate service providers selected by the user are granted shared access to the user's account by the web site system.