To instantly fill your safe, advance the time on your device by a value determined by how much you can currently make per hour. Do not advance it too far to avoid overflows. Set the device's time back to the correct value and repeat as needed. Secure your wealth to avoid using it. Purchase the "Secure your earnings" bonuses for the safe when possible. There are two upgrades. One increases the capacity of the safe and the other determines how quickly your safe fills with money. Ignore the Slot Machine. You will lose money with it.