1. Bolster wear on the drivers seat is quite common so check for that.
2. Good service history will ensure that you end up with a reliable motor.
3. Check for damage or corrosion on the alloy wheels, it has a bubbling effect when it corrodes.
4. Check the rear window washer works its a common fault where the washer pipe falls off and the boot fills with water, its easily resolved with some superglue.
5. Check all the electrics such as A/C, windows and mirrors if it has them.
6. Find evidence of when brakes, tyres etc were changed as the brakes especially are quite expensive.
7. Check for oil in the coolant, and for leaks of coolant around the engine block, it will look like small crystals if any has leaked and dried.
8. Check the condition of the exhaust as these can be difficult and expensive to replace.
9. Check that the multifuction computer works for every reading as it should, it will take time for the car to warm up before it will read an oil temp. Oil temperature should peak in the mid to late 90's with normal driving and the temperature guage should never read more than halfway.
10. Take it for a damn good blast as the 16v really goes mental and its a really good fun