I heard there is a 7% tax on top of the price if purchase a 2 nd hand car from a dealer/tent? Does this apply also if you buy from a private person(not dealer)? 

Only if you tell them

VAT applies to auction sales, not tent or private used car sales.

Of course it does not apply to private used car sales. Vat is only charged by companies that are liable for VAT.

 

There is however a transfer fee.