Zero stars , I got a car that already had 83,000 m...

Zero stars , I got a car that already had 83,000 miles on it to begin with .The total price for it was around $10,000. When I come back to the dealership to get the car appraised ,so I can finance another car with lower mileage. They told me my car is worth 6,000$ !!!!!!!!!!!!!! What the hell , it hasnt even been a whole dam year . So your telling me I'm paying for a car that's 10,000$ and its really worth 6,000$ . Im furious with the used car department ! Im a full time student & I work ,obviously more miles will be accumulated on top of that 83,000 mileage . And u guys tell me the car I'm driving is worth 6,000$ !?! UNBELIEVABLE!