You can also shoot 20x24 B&W. Wisner makes a camera with a standard back and I think S&S makes the holders. $9000 for the camera, $600 for a film holder and $350 for a 25 sheet box of HP5.
or another way to look at it is about $163 a lb at 55 lbs.
I have drawn up plans to build such a camera that would weigh about 30lbs., have full front movements and rear tilt and swing. It is contained in a clamshell design that provides the camera bed when opened and protection for GG and film and holder(s). It would have 40" of extension so it could handle a 36" Turner Riech lens and several Goerz Apo Artars that cover 20x24. But for now the drawings are on the shelf for lack of time. But someday....