@Salami that month I sold 16 cars, I made close to $9k net.
Bonus at the time were $500 for 10, $1000 for 12, $1500 for 14, $2000 for 16. Once you hit 16 you get 5% from the backend (insurance, add-ons and packages).
The old timers were not happy with that chart, the one that was training me told me that with the old rate I could had made over $15k with 16 cars.
And, on used cars, let say the profit margin could be 2500 per car, that goes away pretty quickly. Anything that needs fixing on the car gets deducted from the sales man/front end. So if the car needed a new transmission, the sales man ended up getting a mini as well. If the car only needed detailing and tires, it could net a 2000 profit.