Tips for buying a car! Details below?

So I'm checking out cars so I can buy my second car I'm 21 so I think it's time. I saw this 2010 Honda Accord coupe with 92K miles for $9,900 at the dealership but on Craigslist it says $8,800. When we talked he said that would be the lowest he can go to. I didn't tell I saw it online for the price he "dropped" it to. So should I go back and say online it says it's cheaper? He says if he sells it to me for that price that he's only making a $300 profit and that he can show me the papers that he won't make much I didn't ask to see them but I doubt he's only making a $300 profit. What more should I make him drop it to? And if I trade in my 2007 Honda Accord LX 4 door sedan for the coupe. How much should Be the trade in value for my 07 accord?

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