I doubt very much if david has had much to do with it.
You know how valuable to Porsche it is that beckham drives that just once? He's probably been given it for free looking like that by Porsche when he signed for LA galaxy. And it would have been worth every penny to the dealers/Porsche.
David probably had a 30 second conversation with a publicist/agent and the result was that Porsche.
"hey golden balls, you sure like matt black, right?"
"ye mate"