A:AnswerNo, if you are using your insurance and have an upgrade available you can add it to your plan. Or of course you could always buy it out right. The only reason i think your credit would come in to play would be if you were wanting to sign up for a best buy credit card.
A:AnswerYou can find out who much you will probably get by going to the Best Buy website. You can also bring it with the charger to a Best Buy store be sure to set it back to factory setting before trading it in.