$350 with labor, then there is no way they charged you for 7 hours labor.
Pretty much all Jeeps have to get the bumper cut out for a Mopar hitch, the only exception that comes to mind is the Wrangler. They usually come with a bezel to cover the opening, for the MK its a rubber strip but the MK is fairly easy. You dont have to remove the bumper to cut it out or install the hitch like you do on the WK and XK. I have only done one so far, on a Compass, but that customer didnt want the trailer wiring or cooler since they are only using it for a hitch mounted bike carrier. The hitch itself includint cutting the bumper was pretty easy. I cut it with a very sharp razor knife, just be patient and make several light cuts along the template until you are through. You will only mess it up if you try to cut it in one shot.