360.000 in 20 minutes !
I don't know if your Skyline is powerful enough to race this, but you might want to give it a try:
Enter the Amateur League European Championship.
It's five races with only three laps per race, so it can be completed in less than 20 minutes.
You need to finish first, in the first 4 races, earning 7,500 credits per race,
then save your game .
Enter the fifth and final race, and simply quit out of the race, to end the series. If you finished first in the first four races, you'll win the series, more prize money (30,000,Cr.) And one of four random prize cars.
If you get the Gillet Vertigo Race Car, you can sell it for 300,000 Cr. Thus bringing your 20-minute prize total to 360,000 credits.
If you don't get the Vertigo Race Car, just re-load your saved game, and exit the race until you win the Vertigo. Doing this you can get nearly 1,000,000 credits per hour.
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You might want to keep one of the Vertigos though, because it is a great car, if you tweak it a bit.
Just remember to write down the deafult settings, or save them, before messing with them.
If you are not too hot on settings, you might find some here:
http://www.gtvault.com/
Peace
