How to automatically mount a folder and change ownership from root in virtualbox

If you have the guest additions installed, use the VirtualBox menu:

Devices > Shared Folders...

Add the path, name and enable "Auto-mount" and "Make permanent" options.

Finally add your user to the group with:

sudo usermod -G vboxsf -a myusername

Logout and back again or reboot the machine to complete the process (thanks @Fo).

Groups are stored in /etc/group, according to the usermod man page.

Ah the curse of writing a question and then finding the answer immediately after.

I didn't use the full command suggested in this link

sudo mount -t vboxsf -o uid=$UID,gid=$GID share ~/host

So to add ownership and automatically mount in virtualbox via vboxsf in Ubuntu add to the /etc/rc.local file before the exit 0 line the command as follows:

mount -t vboxsf -o uid=1000,gid=1000 <folder name given in VirtualBox> /home/<user>/where/ever/you/want