That's definitely a creepy person's house. I like the way the house hunters are not aware they are being watched, adds to the creepiness. You could heighten this by adding a couple of bushes into the foreground, really close to the camera with DOF to blur them, just intruding into the image. Keep the view of the house clear but cover the empty lower left corner and allow a leaf or two to intrude over the Aston. Give the impression that the observer is viewing covertly from behind bushes across the road from the house.
The wood texture for the walls of the house doesn't tile, you can see the repeat boundaries maybe try replacing it. All of the textures on the house look very flat; have you set displacement?
I agree that the Aston is a bit too glossy. While I was typing my test render finished so I made a couple of alternative paint finishes:
Might not be exactly the same shade but here's a basic green gloss paint:
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And here's the metallic version:
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