Well, it really depends on the items you're selling. If they're buyables or unpopular event items, for example, you'd be better off just selling the account as a whole.
Don't forget about the gift box capsules, by the way. You could always trade off certain items at the NC chat in return for gift box capsules, get boxes from those, and voila. Free boxes, you've shifted some junk, and you're ready to sell!