My wife and I went in to purchase a 2015 Jetta TDI. The "internet sales price" was $11,999. We offered $11k cash, plus tax, tags & license. They came back with $2800 of "dealer add-ons"; nitrogen tires (hey people, there's 78% nitrogen in the air we breath), window tint, and other hoopla to the tune of $16,977.
My advice... just walk away. There are so many other dealers who are willing to make HONEST offers and not try to swindle you.
Essentially we should have walked out of that dealership $13,250 out the door.