That person is actually not in West Michigan. It's Detroit's own Dan Gilbert. From NBA Champion Cleveland Cavaliers, to real estate in Detroit and Cleveland to area development in both cities and even a train line named after his company, Dan Gilbert (Owner of Detroit based Quicken Loans/Rock Ventures) is Michigan's wealthiest person. Here's the tale of the tape:

Michigan: Dan Gilbert
Estimated net worth: $6.3 billion
Industry: Finance
State population: 10 million
State median household income: $52,492
State’s per capita real GDP: $44,201