That's about £14,000 for the Scirocco, plus your £20,000, so we've got £34,000 to play with. You didn't mention how many seats, but if you need four, this kind of money could put you in an Audi RS4 cabrio or a BMW M3 convertible or a Porsche 911 997 convertible. I don't recommend the Audi TTRS roadster (even though I do recommend the TTRS coupe). Down to two seats and there's the Porsche Boxster S, of course, and the Nissan 370Z roadster, or a used Jaguar XK roadster.