5 - 30 Minuten
My wife's iPhone 4 went through an entire cycle in the wash! Dried it out in rice for about a week. Could only get it to power on via AC, but couldn't actually access the phone.
Took about 5 minutes from grabbing my screwdriver (from iFixit!) to powering on. Unlocked the phone and it started receiving emails and iMessages. Works like the day before the wash.
Be patient. Don't be afraid. Its very easy to repair if you pay attention to the guides here. Enjoy the satisfaction of DIY repair! It also saved us hundreds of dollars in iPhone replacement mid-contract.