Are you actually using more than 100GB or is that just an estimate? 100GB is a freaking lot of disk space usage so i'm betting you are overestimating what you actually need - unless you run some file storage site or something.
If you are going to use that much space, you will might even consider getting your own dedicated server instead.
It sounds like a heavy-duty site if your db is supporting the site. I recommend getting a Windows VPS or dedicated server (if you really need that much space) and install SQL Express (if you don't need advanced reporting services with your sql)
... Windows VPS or even dedicated server will be the best offer for you. Again, shared packages with unlim space - is just a myth, and there is quite
high probability that your account will be suspended or any content will be removed.
As everyone suggested, Windows VPS/dedicated server is the way for your requirements. There are quire a few decent hosts available right here at WHT and a quick browsing through the Windows Hosting forum section along with VPS/Dedicated section will be of good help to you!
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