- 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.