2 - 3 hours
The power button stopped working. You could no longer feel the button click when pressed. My local apple store would have charged $150 for the repair plus I would have been without a phone for at least a week.
I could not find a definite answer as to the part that I needed to fix my issue so for those having the same symptoms you need to buy the "power and sensor cable" for the correct phone model. I also bought the screw driver kit which helped a lot.
The repair went really well. The instructions provided on ifixit.com is what made the difference, without them I've be looking at a completely dead phone.
I strongly recommend that you set at least 2-3 hours aside in a well lit area with no interruptions. On a piece of paper make a grid to hold the screws/parts that you remove while writing down the related step number. Also, take your time!!! Do not rush!!!