Unlock cheat mode:
Before you begin to edit a file, remember to create a backup copy.. Use you text editor to edit the "config.txt" file in the game folder. The cost of every product can be changed. Additionally, you can increase the following numbers to change the starting money for each difficulty.

startkapital(1) = 6000000 ;einfach
startkapital(2) = 4000000 ; mittel
startkapital(3) = 2000000 ; schwer

To get free items, look for the following words in the file and set the values in front of them to "0":

kaufkosten
monatkosten