I love how you guys whine about security costs. FDR spent so much time in Hyde Park and racked up so much cost to protect him and house staff that the feds actually bought the Vanderbilt Mansion in Hyde Park because it was cheaper than the rent costs. His protective detail and staff lived there while they tended to him.
Even beyond the issue of physical security, there is information, access, and communications security as well. I strongly doubt Trump Tower provides a level acceptable to transmit classified briefings between himself and Congress, or the Pentagon, or the NSA. Pence and the Secret Service will have to physically lock him down in the White House/Camp David or otherwise face massive continuing security and protocol breaches.
The more I think about it, Trump will stay in NYC
precisely because it will facilitate access to his foreign handlers.