I live in the Peninsula (San Mateo County, CA). My side of the street is mostly rentals (2BR townhouse duplexes) costing about $4k/mo. The other side of the street is single homes, 3BRs that go for $1.6M. If you want good schools for your kids in the Peninsula, $4k/mo isn't a crazy rent, you might be able to go somewhere else in the area and pay $3k, but maybe you care enough about your kid's future to pay the extra $1k/mo for better schools... so you have a lot of people who are tradespeople or who are struggling to save much after they take care of their kids, but a lot of the homeowners are probably worth $5M at retirement.

My former next door neighbor had to move far away because she just couldn't afford it anymore, but probably at least a half-dozen families on my block could plausibly have net worths in the $5M range. In a neighborhood like this you see $70k and $10k cars parked next to each other.

Why is that interesting? After working for 40 years, saving religiously, it’s entirely possible that they’re living a solid middle class lifestyle not much different from someone else who also lives the same lifestyle but rents and doesn’t save money.