A barrage of new smartphones is about to hit the market, and there\u2019s no better time to sell your old iPhone and offset the expense of buying Apple\u2019s\u00a0soon-to-launch iPhone 6\u00a0\u2014 or any other device you desire. You have\u00a0a number of options to choose from, and in some cases, you can lock in a price today and not have to ship off your phone until the new one arrives.\n\nHowever, you shouldn't wait too long, according to Nik Raman, COO of uSell, which buys used smartphones. Raman suggests prices for the current-generation iPhones will decreases by 11 percent after the two weeks following the iPhone 6 launch; 15 percent after two more weeks; and 21 percent after seven weeks.\n\n Osxdaily.com \nUSell\u00a0essentially acts as a middleman, bringing together buyers and sellers. You go to the site, fill in a bit of information about the device you want to sell, and you get a number of offers. When you accept one, uSell sends you a pre-paid shipping kit with tracking information. A 16GB AT&T iPhone in good condition is worth as much as $240. You don't get much more money for models with more storage. For example, you get just $15 more for the expensive 64GB model. The iPhone 5c is worth around $155, regardless of the storage capacity.\n\nGazelle is like uSell, but it has an additional feature I like a lot. After you accept an offer to buy your phone, you have 30 days to deliver it. That means you don't have to go\u00a0phoneless while you wait for your new device. After 30 days, though, Gazelle lowers the price, and the longer you wait, the lower it goes. As of Wednesday, the 16GB iPhone 5s in good condition gets you $260; if you unlock it the price goes up to $295. If you\u2019re selling an iPhone 5c the prices are $140 and $170, respectively.\n\nCashforiphones\u00a0offers the most money for a 16GB iPhone 5s: $357. However, there might be some risk involved. The Better Business Bureau logged more than\u00a0400 complaints\u00a0against the parent company of the site, Laptop & Desktop Repair, LLC, including many allegations that it performs a bait and switch by giving you a great offer and then finding a reason to pay a lot less.\n\nFinally, there\u2019s eBay. As you likely know, prices on the auction site are all over the place and it\u2019s up to you to cut the best deal. Here\u2019s\u00a0a page eBay devotes\u00a0to selling smartphones. eBay says it \u201cis so sure your phone will sell that for a limited time you get a $100 coupon if it doesn't.\u201d\n\nEven if your phone is in less than mint condition, you'll likely be able to sell it on one of these sites. It\u2019s also worth noting that phones locked to different carriers have different values. In general, Verizon phones have the highest value, Sprint the lowest. These sites also buy Android and other types of devices.\n\n\n \n\nFinally, before you ship off and old iPhone, be sure to\u00a0wipe all of your data\u00a0before you trade it in, even if the buyer-site says its techs will take of it care. You can remove all settings and information from your iPhone, by navigating to\u00a0Settings > General > Reset\u00a0and then choosing the "Erase All Content and Settings" option.