What free market in housing? There are zoning laws, public roads, signage ordinances, building codes, loans and outright subsidies to manipulate businesses into locating one town or another. On the financial side, banks have been (and continue to be) one of the most heavily regulated industries in the nation, next to health care. Government-run Fannie Mae and Freddie Mac now originate a majority of the mortgages in America.
If all that were cleared out of the way, it would be possible for the right kind of person to get the capital necessary to build an entire town. Disney's ideas are probably quite workable, given a truly free market.