Since it's for charity... does anyone know how much could be deducted on taxes (here in the US) from the bid? If you could deduct 50% that means even if you wind up with a winning bid of say 1.4mil you'd be better off than buying the car at current prices.
I doubt that you will be able to deduct anything off your taxes. It would be Ferrari making the donation to charity while you would technically just be buying a car from the charity. Net net, the deduction and tax benefit is Ferrari's.