The kids are basically free (in dollar terms), if the kids go to public school, you don't fly, and you have a stay-at-home spouse who cooks and clips coupons. You also don't have to be wealthy to own property. Outside of major metros, you can get a house for $200-300k, so two houses is $400-600k and the three-unit rental building is probably less than that. And they're probably all mortgaged, not owned outright.