I've been buying stuff on eBay for a while, but I've never sold anything. I'm wondering if anybody on here has, and what I'll need to go about it.

-Should I have the boxes bought already for the items I'm going to sell? (Mostly CDs and video games).
-Where should I buy the boxes for these things from? (ideas? Cheap places?)
-How can I maximize profit on different items? (longer auctions? shorter? etc).

I'm looking to hear back from some experienced members on this and hope some people can help out. I'd like to start selling things right away, but I want to be prepared first.