Finding the right car under $500 down in Union, MO is just a few simple steps away. Each used vehicle in Union listed can be bought with $500 down. Buy a car with 500 dollars down in Union and get an auto loan with $500 down at a single convenient Union Missouri location. Our St. Louis area used car dealers offer you the best chance to finance a used car in Union with a low down payment and a monthly payment that fits within your budget.