I don't think he's the bigly billionaire he claims to be.
Given the debt load carried on Trump Companies properties and the seriously diminished brand value, while I think he may still have fairly tolerable income I would not be surprised that if forced to have honest appraisals, he has negative net worth. What is unknown is how much they have siphoned/stolen from campaign funds and various emolument violations. I simply can't see what is at its' core an organized crime family, spending money they've already stolen/embezzled once just for the chance to steal it back with interest.