Starting to save for real by age 22 is clearly the best course of action, since you'll only need to stash away $287 a month to have $27,540 by your 30th birthday, which is enough for a down payment on an average priced place in Rochester, New York, the most affordable market on the list. Wait until you're 29 and you're looking at having to save a cool $2,295 every four to five weeks to afford the same thing. If you're hoping to put down money on a place in the priciest market -- San Jose, California -- you'll need to put away $2,458 every month starting when you're 22 (or a whopping $19,667 every month for a year starting at 29).
Of course, having a $300 to spare when you're a fledgling 22-year-old with a (likely) low-paying, entry-level job and student loans to pay off isn't realistic for most. But putting away what you can starting as early as possible is clearly a wise move if you don't want to be a slave to monthly rents forever.
Perhaps it's time to consider a career pivot into one of the more lucrative industries. Or, hey, there's always Mega Millions!