Walmart offers the Apple iPhone 6 16GB Prepaid Smartphone for Straight Talk in Gold, Silver, or Space Gray for $399 with free shipping. That's a buck under any other prepaid service for this phone, although most merchants charge $550 or more.

Also available is the Apple iPhone 6 Plus 16GB Prepaid Smartphone for Straight Talk in Space Gray for $499 with free shipping. That's $101 under the cost of any other prepaid service for this model and the lowest total price we could find.