Here's a more in-depth look at the problems with Trump's tweeted promise of "no new deals" as a way of shedding scrutiny over ethical conflicts of interest between his job as President of the United States and his position as owner of a world-wide business empire.
TL;DR: business doesn't work that way, nor do investments.
There’s already a big problem with Trump’s “no new deals” pledge
Trump pledged his business would seal “no new deals” during his presidency. But the company’s many long-standing deals could still help funnel undue money or influence.
Of course, his record of honesty will be enough of a garauntee 😕