Dealer cost was around $600.
I found a wrecked OEM chrome spoiler with a reverse camera. Paid almost nothing.
My car has no NAV.
I installed it and it works perfectly. The only thing is I have to press AUX when reversing (or leave it in AUX all the time). No big deal.
All models regardless of trim levels should have the female connector in the trunk. Pre-wired from the factory.
I traced the wires back to the plug behind the driver's side rear fender above the wheel well.
2 for power I ran back up through the trunk's rubber flexible hose and tapped into the reverse lights.
2 for video I ran through the back seat up under the carpet through the armrest to the aux.
The video cables will be shielded so it's easy to identify.