I would wager "Nary a hiccup."
The market CRASHED when Agent Orange was elected, right up until they realized that there would be unified houses + executive branch, to guarantee tax relief and regulatory reform. That happened at about 3:20am, as I recall it. And BOY oh boy did the buyers come in.
BUT IT WAS NOT TRUMP, it was tax reform.
AND TAX REFORM PASSED. So, "Trumpidiot?" He's yesterday's news. Yesterday was historic: his lawyer testified that he'd performed felony acts with the foreknowledge and at the behest of his employer. AND THE MARKET DIDN'T BUDGE.
That's it.
If either house switches, there will be a downturn, until the market remembers that 1-party democracies are associated with decreased returns, and that non-unified branches tend to produce either *gridlock*, or crisis-responding, legislation. (Meaning: it gets out of the way of business.) We have had our period of *needing* unified government: it has lasted 18 months. By the time we hit the 2year mark???? We'll be better off with a split government. (And the market will know this, and do another Election Night V-bottom: cry "Eeek! Eeek!" and plunge down, and the rip around, straight up, and way past where it started.
TRUMPIDIAN IMPEACHMENT?? NO EFFECT.
((BTW??? Have your passport in good order. If Mother Pence and her hubby end up in de Casa Blanca?? That'd be a great time to scoot.))