An iPad with 16 GB of storage can cost anywhere between $329 and $629 depending on which version you choose. An iPad mini 16 GB that connects to the internet via Wi-Fi is $329, if you want one that also includes cellular services, then it costs $459. An iPad 16 GB with retina display that only connects via Wi-Fi is priced at $499 and if you also want cellular it goes up in cost to $629.
Source Apple Store