How to maximize selling an iPhone 3G?

[jmxflu]

I have a 3G in very good condition and I was looking to sell it on ebay. What steps can I take to get the most money?

Does pre-jailbroken or unlock up the value?

Also, when selling it, I notice how my (ATT) number is in it. How do I get all of my information off of it? Is it something I do on the phone or just deactivate it with ATT?

Thanks and any other tips would be appreciated.