$4000 for a tow bar!

[jammit]

I've just been quoted $4000 by an Aust BMW dealer for a trailer hitch on my 2010 3d!
I called several dealers and they were all within $100.

approx costs:
$2500 for fit of std tow bar
$700 for electric brakes (my boat trailer needs these)
$800 for a LED light module ( my trailer has LED lights)
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$4000 incl GST

This is outrageous. The dealer claims it will take 2 days in the workshop and includes a complete reload of car software which "takes 5 hrs if it works first time". Software upgrade gives rear camera zoom on towball, adjusts the engine coolant program and turns off PDC.
The dealer claims the 7 pin plug is wired with an optic fibre! No wonder it costs so much......

Does anyone else have experience with tow bars in Aust? Is the LED module really necessary?? I took a look at the LED module and its a locally made box with a few resisters in it. How they can charge $800 is beyond me.

It seems I have very little option. I'm sure a $1000 towbar from a local workshop will not be properly integrated into the car electronics....