In terms of buying them in bulk or reselling, no. It seems that their average payout for used iPhones is $149:
- a new iPhone 5s costs around $199 USD with a two-year cellular phone contract.
- a new iPhone 5s costs $650-850 USD without a cellular phone contract.
You can sell your used iPhone or smartphone to them for 75% of the contract price for a new iPhone.
I still can't understand. But thank you all the same.
If you sell them your used iPhone, you will get around 75% of what you have to pay when you sign up for a two-year cell phone contract in the US. Here (not sure about all other countries), most people agree to a 2-year contract with a cell phone company, which makes the phone much cheaper. If I wanted a new iPhone 5s 16 GB without a cell phone contract, I'd have to pay $650 via the Apple Store. If I agreed to two years of service with a cell phone company, it would only cost $199 (which is where NextWorth gets the "can cover on average 75% of the cost of a new iPhone").
It is much better to sell these types of items on sites such as eBay, though - most sites like Nextworth prey upon individuals with fewer e-commerce skills and get them to sell their phones for less.
In a lot of cases, they turn around and sell these phones on eBay! In general, iPhones hold their value really well. As an example, my iPhone (iPhone 4) was worth about $230 before the iPhone 5 was released. As of right now, I can still easily get $180-190 for it on eBay.