I have small children and an expensive phone. As you can imagine, those two things do not mix. Over time, the home button stopped responding and the phone became impossible to deal with. Faced with three choices (upgrade the phone, replace the phone or repair) I chose the least expensive route to try first.
I have zero experience repairing phones. I've repaired computer components in the past (10 years ago) but nothing as sophisticated or small as the internals of an iPhone. Faced with 11 pages of detailed instruction, I decided to go for it. Two hours later, my phone powered up and the home button worked flawlessly. The hardest part was removing the screen from the bezel, and one of the screws (Step 13, 1.4mm screw) gave me trouble, but everything else went smoothly.
Stay organized and don't try to repair your phone with a 3 year old jumping on your back (like I did)
Phillips #00 Screwdriver
Flathead 3/32" or 2.5 mm Screwdriver