I had a quote of wait...... £1100 supply and installation of a towbar kit through VW.
Not too sure what type of towbar it was as I went no further with this after collapsing.
Think it may have been like the pop down version with pull handle in the boot, or whatever.
The dealer did however put me onto a local towbar specialist/spanner who'd do it for about 360quid. I have not gone down this road as yet because I don't fancy some grease monkey cutting a hole in the rear panel and it all going pete tong 
I had a slightly cheaper quote from dealer but it was still expensive so I went to fitter they recommended. Towbar fine but could not code correctly as he did not have the latest software. A complete shambles. Dealer did not want to know..problem with warranty they said, wanted to charge for diagnostics etc etc.
Got the fitter firm to remove everything and got a refund.
Paid another VW dealer £900 for the same Westphalia detachable kit but they coded it correctly and to be honest, I was happy.
The Mk6 system of a detachable piece in the rear valance is not (as yet) available for the Mk7. VW do supply a different valance (£90)! which I have and the hole cannot be seen. Quite neat.
Also got a Thule easifold bike carrier (tow bar) and that is terrific.