Sorry, but beating that out with a hammer will make it look far worse and will encourage rust. There's a big crease, and creases don't pop out. You could, however, have a chance at pressing out the dimple above the wheel arch -- put a 2' long 2x4 behind it and press out. Again, do not beat anything with a hammer.
Also, you fixing it will probably not make it sell better. I'd rather buy a vehicle with a dent than an amateur "fix" that makes it even worse.
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