How to change the amount of money you get from a Family Business object
Open the .package file in SimPe. Filter on Behaviour Function on the upper left, and click on the function called "Charge" so that it opens below.
Select line 2, then edit the 3rd Operand circled in red on the right. Enter the hex value that represents the number of Simoleans you want your family to earn per use. For amounts over 0xFF, use the 4th operand box to carry over.