You can literally sell the 7+ for 550 on swappa...most phones sell within 24 hours.
$400 at gamestop is like you getting ripped off.
Yes....but swappa collects $25. Paypal takes 3% (~20). Shipping, priority, insured with tracking and signature confirmation (USPS) is about $20.
Thus, if it sells for 550, you get about $490. But the average selling price for his phone about ~500, depending on carrier, etc. It is $479 average for sprint at the moment.
Thus, he might only profit $30-40, with $90 being more of a best case scenario.
For some people, the hassle free, risk free appoach is worth it.