President Trump (or more specifically, his creditors) owns large golf resorts around the USA. Presumably, those are all closed due to local directives.
Tens of housands of unused hotel rooms, conference halls, kitchens, refrigeration, intercoms in such locations as Los Angeles, suburban DC, suburban NYC, Miami, Palm Beach, and many others. Simple to transition these to medical rooms by replacing beds.
And, what better place to put a tent hospital than on a golf course where isolation can easily be achieved.
I guess that it would be asking too much for Trump to loan his facilities to the US for use without cost until the end of the COVID-19 crisis.