Placing a reservation on a car you are really excited about is a thrilling experience. However, the experience of knowing your vehicle is being built specifically for you becomes sour when dealership markups take effect and the already hefty price tag gets increased by the price of an entire second car. Unfortunately, that’s exactly what’s happening to some GMC Hummer EV reservation holders when they go to pick up their trucks from the dealership. GMC Hummer EV Seeing Last-Second Markups, Forcing Out Reservation HoldersJalopnik was able to speak to one reservation holder that had this happen t…