15 - 30 minutes
The power button in the iPhone 4S wasn't working and the earpiece speaker when I stopped working
both repairs failed. The button itself wasn't the issue it was the part that pushed up against it and the speaker didn't work out either. The button itself is just a hard piece of metal no issue with it and the speaker I don't know what's going on there.
save your money and just invested in the new phone
iFixit Opening Tool
iPhone 4 and 4S Power and Lock Button
iPhone 4 and 4S Speaker Enclosure