An Audi R10 TDI Race Car '06 costing 4,750,000 Credits. The player initially has 11,162,106 Credits...
...and upon purchasing it, the player now has 6,412,106 Credits, thus earning the trophy.
Sky-High Roller is a bronze-level PSN trophy in Gran Turismo 5. It is achieved by purchasing a car with a price of at least Cr. 1,000,000.