People who buy $500k homes seldom have money.

I'm with Moraen on that.  Most wealthy people in my area have lived in their homes for decades.   The homes may be worth a lot, but that's because they bought the best real estate 40 years ago and have sat on it.  Face it, most wealthy people (other than F500 senior execs) either own lots of real estate or businesses (or retired from).  They have inherited wealth from parents, they are keeping wealth in the family for the kids...much of it due to businesses or real estate.  Wealthy people either stay in their homes and buy 2nd homes (3rd, 4th, etc.), or they buy "big" homes ($1mm+). 

People that buy 500-750K houses are usually 30-45, have kids, a good current income, a big mortgage, 2 big car payments, still paying off those MBA's, paying for the kids' private school, saving for college, and trying to out-run the Jones'.  These people will never accumulate much wealth (other than a few hundred thousend to a million in their 401K by the time they are 65).

I was listening to a guy who said get lists of people who buy the 1million homes,

but there are barely any left in Michigan...

so I lowered it a bit

Dash, here's a better idea....just look up your real estate tax rolls.  You'll see the value of what people own.  You'll see recurring names on the "right side" of town that own multiple properties.  Those are the people you want to target.