Bag yourself a bargain
One not-very-well-hidden cost in upgrading from a DX to an FX camera body is that you’ll probably need to upgrade most of your lenses. It’s certainly true for standard and wide-angle zooms. Another option is to stick with the DX format and to go for a secondhand professional body, with built-in vertical grip and all the trimmings. Some obvious contenders are the Nikon D2x or D2xs, but beware cameras that have been hammered by ruthless pros.