Dev kits are what ever price sopme one is willing to sale it for. I have seen them as low as 600 and as high as 2000.
Unless you're collecting, you can find all the software you need on the internet. This includes the XDK itself as well as the recovery disk for the console.
yeah i know I have a modded retail one. have access to the software and know how to install the xdk dash. but would rather have a real kit. btw which version is this kit? http://www.llamma.com/xbox/xbox_developer_kit.htm lwizardl