Sellalaptop.com Big time scammers Internet

I started browsing around for the best spot to sell my old Macbook Pro and found this site Sellalaptop.com. I started to see how my the would quote me for selling it to them and they originally told me $690 and I figured it was a good deal to go for. After shipping off my laptop and waited to see what they would say and recieve a check in the mail. I recieve a message to inform me that my laptop has dents in it and other cosmetic damage and offer me a price significantly lower than what they quoted me on which was $236. My Macbook never had any dents in it and I have always taken care of my computers. I have had that laptop since I purchased it in Iraq on my 4th deployment there! I wanted to upgrade so I decided to sell it. I had it for 4 years so I wanted to get desktop since I was medically discharged from the Army. Do not trust them at all!