Modern Co.

Buying a used phone can be tricky but with the right tools you could score yourself a great deal on the best phones of last year. Knowing the right sites is essential in your search for that low-price smartphone. For this example we will be looking for an iPhone 6 on any network from a variety of sellers.
Ebay: Ebay is one of the go to sites for people to look for a deal on an older phone. While navigation is quite hard because of the frequent "New" phone listings if you are persistant you can find the deal you are looking for. According to Ebay most iPhone 6's (plural of iPhone 6, I don't mean the iPhone 6s) are trending at $350 however if you are lucky enough to find a $350 iPhone it is almost certain to be broken or in a very bad condition.
Glyde: Glyde is one of the most reliable sites when it comes to purchasing used phones. I personally have experience buying through this company. The pricing is extremely good with an iPhone 6 starting at $419. However there are only several description tiers when it comes to describing the phone and the pictures on the site are of brand new phones not of the actual phone you will be buying.
Gazelle: Many of the same features of Glyde. However it has a much smaller selection of phones and the prices ($419 for an iPhone 6 as well) seem just a little bit higher overall as .
Amazon: Although Amazon isn't specifically designed for used phones it is still a great option when considering its wide selection of used phones grouped by together make and model. The one drawback is that iPhone 6's cost about $435 the most expensive of these four websites.

Conclusion: Glyde is probably your best choice for buying a used phone however if you are looking for a great deal don't forget to stop by at eBay just in case they have a better deal.

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Part 2 (not out yet)