I agree with Stacy. I would add that "concessionaire" is a much less common word, and when used it often refers to a company or person who has a contract to sell products on the property of another person. For example: At a football stadium, the owners of the stadium may have a contract with another company allowing the other company to sell beer at the stadium during games. The beer-selling company would be called a concessionaire.

Hi, Mateo, The correct answer to your question here in North America is 'dealer'. The places where vehicles are sold are called 'dealerships' but they are often simply called 'dealers' (ie. the Ford dealer) Note that the local vocabulary used may differ in other countries. I hope that helps! Stacy