How much do you have to put down on a conventional loan

The minimum down payment required for a conventional mortgage is 3%, but borrowers with lower credit scores or higher debt-to-income ratios may be required to put down more. You'll also likely need a larger down payment for a jumbo loan or a loan for a second home or investment property.

you answered your own : -/

i believe the answer is: returns on investments, no wages

people who belong in upper class society would most likely get there by obtaining multiple source of income, which a certain percentage of ownership for businesses. since most of them are job creator, they would most likely get their money from profit, not wages.