Hosting the G7 has a profit tail attached to it.
"I stayed in the same suite that the Prime Minister of England stayed in."
Also, for a business like a hotel, there are fixed costs just from being open. If the occupancy/rate doesn't meet that in the down months, then you lose money that you need to make up.
Even operating "at cost" (which, itself, is a definitional nightmare), that allows the hotel to keep the doors open and averages out the down months at a higher profit.
When considering the location, his other conflicty problem is grounded in the fact he is what he is: a real estate mogul. Any non-Trump property he picked would be a competitor in the market. No way he chooses a competitor.
Finally, my understanding is that each country pays the expenses associated with their delegation, to include a portion of the security.
The Doral property profitability has been decreasing. Objectively, this will help mitigate that, while depriving a competitor of a huge event.
And he got to choose.
So essentially, he gives considerations to his personal businesses, when conducting the affairs of state?
One other thing, the month when this even will be held, is ,traditionally, the worst performing month for the hotel.