Why not pay for more cloud storage at some cloud provider? That seems to be what you need.
Kees
I have a 1TB drive connected to a spare PC. I have a friend that lives in the same state as I do and we are collaborating on a project.
We were using Google Drive but 8GB is not cutting it as we are saving a lot of HD raw images and videos. I can share my drive easily with anyone in my house, but I do not know how I can share the drive with my friend outside of my home network.
I would actually just like to share only one folder on the drive and he would not have access to anything else. Also I would like to make it so he would have to log in to access the folder, thus keeping anyone else out. I would like to do this for FREE or very cheap but I have a feeling I will need some 3rd party software and have to pay for it. He and I are not opposed to using Ubuntu with setting this up.

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