Trump sends all his expenses through his company. He obviously lives the lifestyle of someone making tens of millions of dollars per year. If he is taking less than $500K per year in income, living like he does, that probably explains why he has been audited 12 years in a row and why audits are ongoing.
Just about all he does is work so I can imagine most of what he does is deductible. It’s just the way the laws have been structured.
I know a thing or two about this.