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Good luck with Ebay. Over the last couple of years the scams have run wild on there. Just watch for selling to someone overseas. Many times you will ship and they will file a complaint with Paypal and you lose your money. Paypal will go with the buyer most of the time.
 
Today, I sold my black 3G 16GB unlocked with yellowsn0w on craigslist in Los Angeles for $375 cash. I think I could have gotten $450 if I would have sold it 2 weeks ago. I have a 3GS 16GB pre-ordered from Apple for $499 for delivery on 6/19.
 
When I sell my 3G, should I include my SIM card? Shouldn't I take it out and use it with my new 3GS? Will I have less of a chance of selling it if it doesn't come with the sim card?
 
When I sell my 3G, should I include my SIM card? Shouldn't I take it out and use it with my new 3GS? Will I have less of a chance of selling it if it doesn't come with the sim card?

You don't want to give your sim away as that is what links you to your account. Keep your sim for your new phone. Your buyer must provide his own sim.
 
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