I've often wondered why somone moderately wealthy doesn't just start a super dense town, e.g. everything within 100 acres, and be within 10 miles of a major city. Create tons of these at a 50K people/sqmi density and implement some sort of hub spoke transportation with the major city being the hub and it could work!
Interesting, what would incentivize people to live there, as opposed to the city?
Otherwise I guess you could just make it cheap. For those reading -- what would incentivize you?