Here are the latest estimates (last updated March 2008) of how much the station and its ancillary development will cost, and who will provide the funding.

Cost
$3.2 billion: Total cost of Moynihan Station (East and West)
    $900 million: Moynihan West (excluding the cost of the new Garden arena)
    $2.3 billion: Moynihan East (excluding the cost of the 1.1 MSF of retail)

$14 billion +: Total cost of all development - the train station, the new Garden and 8 million square feet of retail and office space in the neighborhood

Funding
The following sources of funding have been identified for the $3.2 billion station:

$900 million: state and federal funds already authorized and appropriated by Senator Moynihan for Moynihan West
$550 million: committed by the Joint Venture of Vornado and Related (the developers)
$300 million: committed by the State, though Gov. Spitzer offered to increase this amount up to $500 million if the City did the same
$300 million: promised by the City
$500-800 million: anticipated from the federal government

This leaves a gap of up to $650 million, which will have to be filled by the developers, the City and the State.

This funding gap is not insurmountable, but it is one more reason for the Farley building to be renovated in a way that qualifies for federal historic preservation tax credits, which could be $230 million.

Note: Madison Square Garden is paying for the construction of its arena. In fact, the Venture is paying the Garden to move because it will be buying the air rights over Penn Station that the Garden currently owns.

Read more about:
The current plans for Moynihan Station and the surrounding district
Project timeline