Why? Just curious.

 So I couldn't be accused of selling car with electrics not completely set up for towing, i.e that automatically turn off the eco mode when anything is connected to the tow bar. Personally I could live with making that change manually, but morally probably shouldn't in case the next owner assumed things would happen automatically. I'm going to ring round some of the smaller dealers again to try and get below the quoted £560!

 So I couldn't be accused of selling car with electrics not completely set up for towing, i.e that automatically turn off the eco mode when anything is connected to the tow bar. Personally I could live with making that change manually, but morally probably shouldn't in case the next owner assumed things would happen automatically. I'm going to ring round some of the smaller dealers again to try and get below the quoted £560!

Puzzling theory, all the new owner needs to do is add a new swan neck and your electrics are being used again, best bet would be to remove everything before you sell it, also that way you can sell a complete towbar.