"BACK IN 2000, when Donald Trump was considering a presidential run on the Reform Party ticket, he told Fortune, "It's very possible that I could be the first presidential candidate to run and make money on it." And though it's hard to say whether Trump has actually managed to turn a profit (at least not without getting a look at his tax returns), according to his re-election campaign's FEC filings, Donald Trump is sure as hell trying his best.
Even though Trump is, in fact, the current president, he only stopped running for a brief few hours on Inauguration Day. As soon as Trump filed for re-election, at 5:11 pm on January 20, his campaign officially sprang back into action. That means Trump can legally continue to funnel funds from donors back into his own businesses. According to the Trump campaign's self-reported FEC filings, this has amounted to about $600,000 spent at Trump-owned properties in just the first six months of his presidency..."
https://www.wired.com/story/trump-2020-campaign-money/?mbid=nl_72217_p3&CNDID=14244234
I've read elsewhere that Trump paid Jr.'s lawyer out of 2020 campaign funds...and now thinks the RNC should reimburse him.