You can buy fractional shares of mutual funds. Vanguard only lets you auto-invest on a schedule into mutual funds. Mutual funds trade once a day, at the end

You can buy fractional shares of mutual funds. Vanguard only lets you auto-invest on a schedule into mutual funds. Mutual funds trade once a day, at the end of the day, for the intra-day-valume-based average cost so you are not timing the hour.