My iPhone 3GS has some scratches on the back & the bezel, and some dust particles has also gone under the screen. Home button has also become insensitive. The warranty is long over & never had any AppleCare & stuff. Is it possible that I bring this phone to an Apple store & pay them to help me refurbish my iPhone? I still want to use my iPhone, don't want to upgrade & willing to pay for the refurbishment.