Isn't it hard to find a house if you live in the metropolitan area?

I live in Changwon, and I can find a decent apartment for 500 million won.
500 million won isn't a small amount of money either.
For those living in the metropolitan area, how do you afford those expensive apartments?
It must be difficult even just paying off the loans.
I have a friend in the metropolitan area, but they settled down when they were very young.