Since Mr. Banks had 8 investment streams and each brought in a revenue of $500, he earned 500*8 = $<<500*8=4000>>4000 from all of his investments.
Ms Elizabeth also received $900*5 = $<<900*5=4500>>4500 in revenue from her 5 income streams,
The total amount of money that Ms. Elizabeth made more than Mr. Banks is $4500-$4000 = $<<4500-4000=500>>500
#### 500