Quick once over before selling, the cheapest & easiest way?

[-Pete-]

I'm expecting all sorts of negative responses, but I'll give it a go anyway. I'm going to be selling an 18 year old car soon, and want to make it look less tired without spending too much time or money. For arguments sake, let's say 2.5 hours and £25. Obviously I'll wash the exterior and wheels, hoover it out etc. What's the cheapest & easiest way to make the interior & exterior plastics & rubber look tidy? Is Turtle Wax 'Black in a Flash' any good? Does CarPlan Demon Shine do anything? What about the dashboard and door trim?