There's like a point where money doesn't raise happiness. But up to $50,000 it has a huge impact and does "buy" happiness. So whatever amount enables you to live a comfortable life (I'm sure 50k does nothing in a city and the point must be much higher.)
Beyond that one study, don't most/many marriages end because of money? If all those couples made more (or even in some cases, an equal amount) they might still be married and happy.
Edit: One of my favorite rich people concepts is the whole "they have so little and yet are so appreciative and love life" (just to mention the opposite of this thread.)
