Walmart offers the 4th-generation Apple iPad with Retina Display 16GB WiFi Tablet in Space Gray, model no. MD510LL/A, for $349 with free shipping. Outside the price below, that's the lowest total price we could find by $50, although it was $20 less two weeks ago.

A close price: Chubbies Tech via eBay charges $349.95 with free shipping. While new, it ships in an aftermarket box.