Buzzfeed reports Trump signed a letter of intent for the building of Trump Tower in October 2015 , the same day as the third Republican Debate
On Oct. 28, 2015, the day of the third Republican presidential debate, Trump personally signed the letter of intent.
In a celebratory email sent from his Trump Organization account, Cohen asked Sater and Rozov that the “nature and content of the attached LOI not be disclosed” until later and said “we are truly looking forward to this wonderful opportunity.”
The deal stayed open through at least May 2016, as Felix Sater and Michael Cohen worked to try to get financing and otherwise push the deal through.