That's still a substantial sum: A one carat engagement ring typically costs around $5,500. 3 But most couples have no idea what diamonds cost: they set out to spend between $1,000 and $5,000, yet the average cost of an engagement ring ends up being over $6,000. 4 Statistically, spending for engagement rings has a long tail: 7 percent of. New York City — To live comfortably, you'd need $131,365 in Brooklyn, $169,639 in Manhattan, and $116,907 in Queens. 8. Los Angeles — $102,061 would have you sitting pretty in LA.