In most area's the maximum VA loan amount is $417,000. But the VA allows for larger, "Jumbo", loans up to $1.5 million! There is no down payment requirement for loans up to $417,000. Loans over that amount require a 25% down payment but just on the amount over $417,000.
So on a $500,000 the required down payment would only be $20,750 ($417,000 x 0% plus $83,000 x 25%). A standard Jumbo loan would require a 25% down payment on the entire loan amount, $125,000!