The use of Federal Historic Rehabilitation Tax Credits to finance a portion of the proposed development of the new Farley-Penn Station is an excellent idea. In fact, since 1998, CityScape Capital Group has encouraged the Municipal Art Society of New York to pursue Historic Tax Credits for this project. While the Wall Retention Test doesn't apply to the 20% Federal Historic Rehabilitation Tax Credit, the project will still need to satisfy the Standards for Rehabilitation and receive approval from the National Park Service (which is much more stringent than the Wall Retention Test that applies to the 10% rehabilitation tax credit for non-historic commercial buildings built prior to 1936). The project will also need to address tax-exempt ownership and usage issues which may ultimately result in a reduction of the qualified rehabilitation tax credits. Even though the Related Companies will probably syndicate the tax credits themselves, CityScape Capital Group stands ready to assist with the tax credit syndication process. Best of luck with the project!