Ourisman Chantilly Toyota

I purchased my last two cars from Ourisman. I was pretty happy with my experiences. Last night after much research we decided to buy a new Corolla from their Chantilly location. I was trading in my most recent purchase a 1996 Miata MX5 with 58K miles. I had just pourchased the car from their Fairfax location with in the last year. I blue booked it on line in good condition and expected to get $5k in trade. Low and behold when they gave me their trade value they stated the car was only worth $1500. I understand the "caveat emptor" theory. I support businesses making a profit. However, I feel as though I was really taken for a ride in this case. I could have and should have not purchased this car. I can no longer recommend this dealership for these unethical behaviors. I thought the automobile industry had turned a corner. Evidently, not.