Cars having no VAT in the price:
All cars which have been owned and registered once by private persons have no VAT in the selling price. No matter who is selling them now. No matter how old a car is. Private persons have no tax accounts and can’t sell with VAT. Private sellers will sell a car with a sales contract but it will show no VAT.

Even if such a car is now sold by a dealer. No deductable tax in the price.

Cars selling with VAT:
Used cars owned by companies or financed / owned by a bank or leasing company are selling with VAT (German name: Mehrwertsteuer, MwSt). A tax return is possible when exporting such car to a country outside the EU. It need a proof. 
If you buy such car with my assistance, I can get it for you for the net price, tax-free. But in that case I have to do the buying, the German customs declaration and the shipment to your country.

If you buy the car yourself from a German dealership you will have to pay the brut price, including the salestax first. You can claim a tax refund from the selling dealer once you exported the car to your country. You have to send the export documents to the dealer to confirm that your car has left the territory of the EU. Please discuss that with the seller before buying the car!

If you search German internet sites for used cars you will clearly see if the car you found has VAT in the price or not. It is always marked at the price tag. Our VAT (MwSt) is 19%. Price tag should show net and brut price.

Sales inside the EU:

I am exporting cars to countries outside the EU only, can't give much information on EU sales. But you need to have a business in your country, need to show a company registration, a tax ident number, a passport copy of the owner, a confirmation of the transport company. Once the car is registered in your country you will need a Confirmation of Arrival to proof that you have paid taxes in your country. With all that you can get a VAT refund at the German dealership. Please discuss that with the selling dealer before buying the car...

Some German dealers have had bad experiences with EU sales because the documents they received were fake. Some therefore reject EU sales.