This Penn Station "bid" (January, 2016) is a recent example of New York City's solicitation for private  developer proposals to redevelop the "Farley Post Office, located directly across Eighth Avenue from Penn Station, (and) will involve fixed-price construction of a 200,000-square-foot train hall, featuring shops, restaurants, about 700,000 square feet of office and retail space, and potentially a hotel".  The U.S. Department of Transportation, the Port Authority of New York & New Jersey and Amtrak would pay a total of $325 million. The remainder would be funded through private investment in exchange for the right to develop, operate and collect rents on retail and commercial space in the complex.  It's quite a large project, but again the ridership/customers and retail income reflect a mega-urban center like New  York City.  http://www.ncppp.org/new-york-issues-joint-solicitation-for-development-of-penn-station-post-office/