What's a 69 Dodge Dart /6 worth?

I went and looked at the car. Come to find out it's a 69 with a 68 grill. The car has rust at the corner of the rear window that has pushed up and cracked the paint. There is also rust on the rear quarter panel. The paint has been eaten away at the gas cap from gas leaking out. The interior smelled pretty bad of mildew and a rat made a large nest in the driver floor. Other than that the interior wasn't that bad.
Anyway, I offered him $800 for it. I thought that was a very fair offer. Well, he kept saying he wasn't sure what he wants to do with the car. So, I took that as a no. That's fine because just up the road from him there sits a Sassy Green Mopar with a matte black Hemi scooped hood. The funny thing is, I don't know what it is. I plan on going back and talking with the guy. Another one of my friends says its a Fury but, I don't think so.