I bought an iPhone 5 off CL for a great price and it functions perfectly. The screen is flawless with no scratches or off-color hues. I noticed the bottom screws have some wear on them so I assume the unit has been opened. I know this because I've replaced the battery myself on my 4S. Could there be any possible reasons other than the original owner replacing the battery? Granted they didn't mention this in the ad because they probably didn't want to scare away any buyers if they knew the unit had been opened by non-Apple personnel but I don't mind because I've replaced batteries on my iPhones all the time. Would this be the only reason?