Assuming 10% down? Why would you assume that?
What’s 10% and a half a million dollar home? $50,000?
Where in tarnation are a couple making 60k a year between them, going to get $50,000 cash? For the most part, I can assure you, that’s not happening for the huge majority!
Lots of ways. 1) Savings 2) Sold another house and rolled over equity 3) inherit money 4) money from family 5) 401k loan; etc