• edit the file
    C:\Users\adminuser\AppData\Roaming\NetBeans\8.0.2\config\Preferences\org\netbeans\modules\projectui.properties

  • set the key/value
    lastOpenProjectDir=C:\\Java\\NetBeansProjects

  • Create project and chose Project Location = C:\Java\NetBeansProjects

Next time, when creating new project, the new project location will be set.