A goooood chunk less than 150m...since you can get a 30% card at any time in the Millionaire center....and less than that if you shopped around.
There's not a whole lot of demand for it - i've put a 10% and 20% in trades from time to time the past year or 2 with no offers. SubetaLodge price history has it going from 15m - 44m the past year. Which sounds pretty reasonable 15m would probably go realllly fast - so try higher than the 44m if your not in a hurry.