Originally Posted by TripleBlack
You and the OP should search youtube for fixes. I don't know about the power button but the home button has two different fixes that don't need you to open the phone.
+if its a software issue thats stopping the home button from working, you need to re calibrate the button search youtube for iphone 4 home button software fix
+if it is a hardware issue you need to a rub a small bit of strong alcohol like vodka into the crease of the button. Press it a couple times, tap it out, let it dry. Then it should work.
I tried both on and the second one solved my problem. That was 4 weeks ago and its working as new still.
If neither work and you still don't want to pay to fix it, you can activate the 'virtual home' button via the settings.
Again, I don't know about the power button but it could be some dirt stuck in there that a bit of alcohol can remove.
Thanks for the suggestion.
I have activated the virtual home button and been using that since it decided to break. I will give the alcohol method a try and see if that has any effect.