I am planning to buy an iPhone 4. My wife already has one. I feel iPhone 4 will suffice my needs and I don't really need the 4S or the next iPhone. So should I wait for the next iPhone to be launched and then try finding the iPhone 4 on eBay etc ? Or buy now itself ? Can I expect prices of iPhone 4 to further drop after next iPhone launch ? I want minimum 16 GB so the 8GB won't really cut through. Also what is the going rate of used iPhone 4 as of now ? And last and most important I need the phone to have a real unlock as the phone will be used outside USA.