Hi Marky - welcome to the site.
Im in Epsom with a similar age 56 ZED. From the ad:
NISSAN 350 Z 3.5 V6 313 GT 3DR UK CAR, 3 Doors, Manual, Coupe, Petrol, 2006 56 Reg, 15,900 miles, Metallic Black, 1 Owner. ABS, Very Low mileage, Alarm, Audio remote control, 18 Inch Alloy Wheels, Navigation system, Xenon Headlights, Full Black Leather, Body coloured bumpers, Park distance control, Central locking, Climate Control, Electrically adjustable seats, Cruise control, Heated seats, Electric door mirrors, Front electric windows, Front fog lights, Front head restraints, Headlight washers, Height adjustable drivers seat, Immobiliser, Leather seat trim, PAS, Passenger airbag, Radio/CD Multichanger, Rear wiper, Remote central locking, Side airbags, Sports seats, Steering wheel rake adjustment, Traction control, Trip computer. Bose Sound System. One Private Owner From New With A Full NISSAN Service History. UK Car With Manufacturers Warranty Until 04/10/2009. A Stunning Car In Remarkable Condition.
From the pics it looks totally standard and seems OK. But insist on a good hour or so drive as it will feel so different than what you have been used to - in a good way You are likely to find stone chips around the front end - we all get them - Nissan paint quality is not good The skipping CD issue is genrally only when the car is cold - condensation is blamed. But just enjoy the sound the car makes - much more satisfying
As others have said it is a 296 bhp engined model not the 309bhp (313 is the ps not the bhp)
The paint is Ebisu - it is metallic but the flake is difficult to spot when it is not sunny.
The headlights are bi-xenon - a whole lot better than the pre 2006 standard xenons (I have had both and there is no comparison)
There are no front fog lights!
And providing the service record is sound, you've got 7 months or so to get any probs sorted, but you might like to haggle for an extended warranty in this buyer's market