Trump inherited his wealth, and relied on grift like
Trump University to "grow" his net worth before becoming POTUS:
Lucky Loser review – how Donald Trump squandered his wealth
"Donald Trump started his career at the end of the 1970s, financed by his father Fred Trump.
"Over the years this transfer of wealth added up to around $500m in today’s money in gifts.
"My rough calculations say that, had he simply taken the money, leveraged it not imprudently, and passively invested it in Manhattan real estate – gone to parties, womanised, played golf, collected his rent cheques and reinvested them –
his fortune could have amounted to more than $80bn by the time he ascended to the presidency in 2017."