You've got a good chance at this going through for you especially if you've got that price in writing. About two years ago I knew a girl who went in to buy a used saturn and signed all the papers and they messed up on the price on the quotes that she had signed. Well, the next thing they did was tell her that they messed up and that was the wrong $$$$$ that she got quoted. She told her father they went down there together and threatened to take them to court and blah blah blah...... After that they decided to just give it to her at that price and eat the diff. rather than spend money on lawyers and end up losing anyway, so she got the car for like eight or nine grand less than the list price.
So the outcome looks good for you especially if your lawyer gets involved........ Why can't I have your luck
