Should I include or exclude Original content storage in calculation for what SSD drive size to buy?

Considering buying an external SSD to hold all my MEDIA, CACHE, and MOTION CONTENT. What's the total size currently used? I've already Consolidated my Media and Motion Content. So does that mean I should include or exclude Original content storage use in my calculation for what SSD drive size I need?

Go to the Finder, select a Library, Command-i to see its total size. Also, plan on future Libraries and productions you'll be doing. You're talking about an external SSD, right? You're not putting this all on your system drive, I hope.