Look through the records of the most expensive cars ever sold at auction and you'll see Bugattis, Duesenbergs, Aston Martins, Alfa Romeos... but the one model line that pops up again and again is Ferrari
's 250 series. Comprising the bulk of Ferrari's models during the 1950s and 60s, the 250 series included such notables as the GTO, Testa Rossa, Lusso and California Spider. But just as vital to Ferrari's dominance of sportcar racing in its heyday was the 250 GT SWB. And RM has got one going up for auction in Arizona next month.