I got in a car wreck and the other car hit my rear passenger door. It is all smashed in and the window is shattered. Im no car expert but it just looks like its too damaged to be fixed. How much would it cost to replace the whole door with a new one? And how would i go about doing this?

1999 Mazda 626, Car Expert, Car Wreck, Mazda, Mazda 626, Rear Passenger