Cautious of buying a preown with supercharger?

[Sneakygoat]

Hey guys,

Brand new to the forums, been trolling for awhile and finally figured it was time to register.

I am currently seeking to purchase a Z and recently found one about three hours from my home town for sale via a dealership.

It's a 2009 370z Touring edition. It has 25,000 miles on it and they were asking 28k and now I see it just went down to 26K

The catch is that the web ad claims it has a "$8000 supercharger giving the car 500HP". There is about 10 photos of it and across the top of the windshield it does in fact say "Stillen".

Now I am fully aware it could very well have a supercharger in it but had no idea they ran $8000 unless this is just a sales ploy. Also it's an automatic which my limited research has told me that superchargers and autos don't really go together that great. Lastly, since it has a supercharger on it would that void any factory warranty?

Any thoughts, concerns, or advice would be greatly appreciated!