The $750 income tax thing shouldn't be surprising to accountants and attorneys (at least those who have encountered tax law). Trump's has huge real estate holdings. It's really his entire business. If I remember from my basic tax law class, in real estate, you can take depreciation every year on your taxes. This would offset his income with losses. However, it also decreases your basis in the property so you realize more income when you sell it. However, that income is taxed at more favorable capital gains rates.
So if Trump has skilled accountants and tax attorneys, they'll probably have his depreciation resulting in very little income tax liability. However, I'm not sure how much of the depreciation benefits would accrue to Trump and how much would accrue to his companies. I don't know how he has things structured.
There's also no telling in exactly what way Trump has his income set up with his companies. You can bet it would be in the most tax favorable way possible.
The $750 of income tax makes great headlines but it's not as crazy as it sounds. If anything, it should be an indictment of our tax system,
