Replying to Filmmakers: when do you delete your files?

So i have this problem that has been building, I have two 1tb external drives full, one 500mb full, and my computers 500 mb almost full as well of mostly raw video files. For most of them I have already made the edit, and used the best of the shots in my cinematography reel, but I just can't bring myself to delete them. For some reason I feel like there may be a time I will need some random clip in the future and I cant get myself to do away with them. This would not be a problem except for I am not really able to afford any more harddrives at the moment, so therefore I think it must be done.

Basically what I am asking, is do any of you other filmmakers have this problem? and If not then at what point will you finally get rid of files? I feel like a hoarder, except in the digital realm haha.