Purchase of vehicles for commercial use only (SUPPORT)

Hello all, I found a used car at a large car dealership. The car has run over 200,000km and is sold only to traders or exports. I want to buy the car for export, just as a private person. The dealer insists to sell as his own protection only to traders. My sister has a business, I could run it over you. How does it work with the tax office then? Since the vehicle goes abroad within a week. Are there any difficulties later? Thank you in advance!