Cellfeee via eBay offers the refurbished Unlocked Apple iPhone 6 16GB GSM Smartphone in Space Gray for $349.99 with free shipping. That's $80 under our mention from September and the best price we've seen for an unlocked iPhone 6. (It's a current low by $50.) It's compatible with GSM networks such as AT&T and T-Mobile.

Note: No warranty information is provided.