Let me try to explain:
All listed prices for brand-new cars and those with a company registration include 19% German sales tax (MwSt - Mehrwertsteuer = VAT - value added tax). If cars are sold by private persons, German sales tax cannot be deducted from the price when the car will be exported.
If you buy a car (with former company registration) from a dealer he will give you the net price by deducting 19% from the brutto price. This is very important for you, when you are not an EEC-citizen i.e. you pay only the net price.
In some cases, when you pick up the car yourself at the dealers place, you would have to pay the full price, but the tax will be refunded later by the dealer when the car is exported and the “customs-clearance-certificate” is presented to the dealer.
Please be aware that most used cars have private pre-owners, hence no refundable tax.