In rural Illinois you'd pay $500/month mortgage on a reasonable 3 bedroom home in a safe middle class neighborhood, in Dallas you'd pay maybe $700, in Albuquerque you'd pay $800, in Miami you'd pay $1200. So, the biggest gap there is $700/mo. That's $8,400 a year.
In suburban NJ you'd pay $2000. Plus another $1000 in taxes. In Silicon Valley you can double or triple that mortgage payment. You just haven't included the highest-priced markets.