Bare flange type (not detachable ) towbar from P F Jones less than £80, depends if you need 7 pin or 13 pin type socket, and with CANBUS electrics you'll need a dedicated or a bypass relay, so you'll not get much change out of £130, leaving plenty for labour costs, but personally as it's an easy fit I'd do it myself. No need to remove or cut bumper and fitting time (towbar only) 30 minutes.