In order to do this cheat you must follow these steps.

1. Spend ALL of your money until it's at zero

2. Then the tax menu comes up at the end of december, hold down the L button, then lower the transportation, police, and fire to zero.

3. DONT LET GO YET. Exit the screen, don't let go yet.

4. STILL HOLD L. While holding L go to the tax menu again raise all of the things back to 100.

5. DONT LET GO. Exit the screen again while still holding L, not let go of it once your out of the screen then press X. If done right you should have $999,999.

This may or may not work on the wii version but, On the SNES version there was a cheat to give you $9999999. This was how it was done. Wait for the budget plan in december to pop up. Hold down L and R and don't let go until I say you can. Lower all funding andthe Tax Rate to 0%. Close the budget window and open it again this time raising the funding to 100% and the tax rate to 7%. Close the budget window. NOW YOU CAN LET GO OF "L" AND "R". You money amount should now amount to $99999999. You can repeat this every time it runs out giving you the ability to do cool things like use tracks instead of roads and use Nuclear Power instead of Coal plants and having 0% TAX RATE!!