I recently lost an iPhone 4 . I am eligible for an upgrade now but was planning to upgrade to iPhone 5 when it becomes available. I need a replacement in the meantime. It seems like my options are: 1. Find a replacement on Craigslist, eBay, etc. Pricing seems to be $350-$400 for a white 32GB iP4 in pretty good condition. 2. Upgrade to a 32GB 4S with a 2-year contract price, $299+tax. 3. Upgrade to a 32GB 4S with no contract, $750+tax. Can you help me decide what is the most cost-effective way to go, if my goal is to get an iPhone 5 when ever it comes out and sell which ever I get in the meantime to recoup costs? Thanks!