We need to separate out Trump pre-Presidency and since he first became President.
Before he was President, Trump was a clownish figure amongst real businessmen, known for making terrible deals. He had bankrupted almost every business he had ever set up and his remaining projects were haemorrhaging money. The only thing keeping him afloat was his stint on reality TV, playing a fantasy version of a successful businessman.
Since becoming President, he has very successfully leveraged his status to become very rich. Mainly by selling tat to MAGAs.