The commission can put an extra $300 to $400 in a salesman’s pocket per car sold, and the average salesman sells ten cars per month. Manufacturers up the ante by rewarding dealerships and salespeople with cash for selling certain tough-to-move models, and add bonuses for hitting volume targets.he program upends the traditional salesman setup, promising recruits ways to move up fast and pay that isn’t based on commissions. Salary is set at $30,000; bonuses are paid monthly and based on units sold. Sell seven cars in a month and you get $25 per car, or $175. The incentive is to push cars, not the price.