Here's an option you might not have considered, but might be applicable, depending on the read/write speeds you need from those hundreds of gigabytes of data. Amazon has cloud drive, which costs something like 50 bucks a year, and has unlimited storage.

The neat thing is someone created a FUSE file system called acd_cli that allows you to use the cloud drive as if it were a normal hard drive. The speeds aren't too shabby either; I easily get 150MB/s up and down on my dedicated server, and response times are snappy. Additionally, you can create a unionfs mount so that writes are instant, and you sync new files on a regular schedule.

Of course, that might not be applicable to your use case, but I use mine for many things. I have a plex server running using that with over 13TB of videos, and it works flawlessly. It allows me to run a full plex server with unlimited storage for 20 bucks a month.