We are using VirtualBox as local Linux development server too, but we use a more simple setup. We allowed VirtualBox to access our Windows development folder (see VirtualBox shared folders) and hooked our Windows development folder as document root folder for the linux apache using a symbolic link.
Now we can just save our work in Windows and our local Linux Server is always up to date.
If you have any issues this forum thread helped us during the setup:
forums.virtualbox.org/viewtopic.php
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