I'm developing a mobile web app but only had iPhones and wanted an inexpensive, rugged Android phone for testing. Got an Amazon renewed Oukitel WP5 for about $115 - the new ones were around $140. It was sold and shipped directly from Amazon, which is why I decided to take a chance. In short, it was perfect and had all the original accessories.
I was very concerned when it arrived, it was shipped in one of those heavy plastic (kevlar?) bags but when I opened it, there was a huge hole in the side of the box, like somebody had poked it with a pointed object. Almost returned it without opening the box, but decided to check it out. Everything was fine inside the box so I'm pretty sure this was a new item that was returned by the previous purchaser because of the damaged box. I guess Amazon checked it out and decided it was actually OK.
Anyway, the phone has been fine. Now, I only use this from time to time for testing my app, it was cheap and saved me some money, so I'm quite happy. Would I buy an expensive Mac this way? Hmm... probably not, although if it's sold and shipped directly from Amazon, it seems like you have pretty good protection.