this is a job for the media manager. right click the media and select media manager. there you can copy, move, recompress, use existing and make media offline. It shows you how much media you are ending up with. You can chose to use this tool with a sequences as well. Once you are finished with your edit you can delete unused media and keep handles on your clips for fine tuning and possible additions of cross fades later.
It’s fun and once you use it a couple of times it’s not that scary.
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