1. My own 240sx (20k when it is done)
2. Ferrari F40 (whatever is left should be enough My all time favorite car)
3. Titan (46k with the options I wanted)
4. Honda Civic 4dr Si (29k daily)
5. Ariel Atom (55k weekend car)

500k is not enough....

If this is unlimited on money, this would be my list

Ferarri F40
CLK-GTR
Rolls royce Phantom
Ford GT
NSX-R, GTR R32, or Fit for daily