Yapper Wireless via eBay offers the refurbished Unlocked Apple iPhone 4S 16GB Smartphone for GSM Networks in White, model no. MD237LL/A, for $149.99 with free shipping. That's $20 under our mention from two weeks ago and the lowest total price we could find for a refurb by $19. It's compatible with GSM networks such as AT&T, T-Mobile, and Vodafone; it can't be used with CDMA networks such as Verizon or Sprint.
Note: No warranty information is provided.
Need a Verizon phone? As we mentioned five days ago, Groupon offers the refurbished iPhone 4S for Verizon or Page Plus for the same price.