The cost of which he would set against his tax as most are self employed having set up a company, so the actual cost would be next to nothing. The down side is that he would probably have to make do with a Jag, BMW or Land Rover as opposed to a Ferrari or similar.
It always amazes me that these types who like a drink do not employ a young chauffeur who wouldnt cost a lot and be at his beck and call when required. I remember as long ago as his days Peter Osgood did and the young chap swanned around like it was his car in Epsom.