Monopoly

					
Cheaper Property
When playing against a single computer opponent and when you're at an auction simply bid 1 above your opponent. He'll give up on the second round.
Extra Money
Start the game as usual but select three playings on controller 1. On your turn make deals with each fake player for their money. When it's a fake player's turn go to "Bankrupt" with each of them. Now you may play the computer with a little extra money.