When the game saves your progress in a slot it creates two files, one of them is a plain text file. They are named slotx.cmb and slotx.cmf, the plain text file is slotx.cmf, the x is for the slot number in the game. Open the .cmf file in any text editor, notepad will suffice. Search for currentcash, check that this is for player1 and simply replace the ammount for however much you want. The file contains many variables for pretty much everything but I'd imagine that the cash is all you'd need to alter for easy gameplay.