Thinking of selling my 2012 Z

Lefix

I see you have the rays so assuming you have sports package and base model.

KBB puts your car with 35k miles at $15977 for fair and $17356 for very good.

If it's purely cosmetic, with no structural damage, looks like you need:

Passenger headlight
Bumper
Passenger fender
Passenger mirror
Maybe bumper brackets or inserts
Under body plastic covers
Hardware
Installation labor and paint

Even without structural damage it would need to be assessed for alignment.

With an aforementioned 15-20% further reduction since the buyer has to get the work done, you'll probably be looking at $8k-$10k for it.