Here’s one more thing for investigators in the Russia probe to dig into.

The top ranking Democrat on the Senate Finance Committee, Senator Ron Wyden, has called on the Treasury Department to start digging into President Trump’s finances.

Specifically, he has an interest in the banking and real estate records for the sale of a Palm Beach mansion to a Russian billionaire.

Trump sold the property in 2008 for $95 million to Russian oligarch Dmitry Rybolovlev, after purchasing it for $45 million four years earlier. Trump has attributed the flip to renovations he made on the property. At the time it was considered one of the most expensive house sales on record.

“It is imperative that Congress follow the money and conduct a thorough investigation into any potential money laundering or other illicit financial dealings between the president, his associates, and Russia,” Wyden, D-Ore., wrote in a letter to Steven Mnuchin, the treasury secretary.

So what was so unusual about this very expensive sale (other than the Russian buyer, that is)?

As Wyden points out, at that particular time, Trump was bank-hopping, trying to find a bank to lend him money and was getting nowhere. No banks were willing to front him cash.

A few months after the sale, Trump Entertainment Resorts filed for Chapter 11 bankruptcy.

It could be nothing. It might be something, but Wyden wants to know, for sure.

Wyden is part of the Senate Intelligence Committee, which is investigating Russian meddling in the 2016 election and whether the Trump campaign colluded with Russia to influence the outcome. Rybolovlev is being looked at by special counsel Robert Mueller, according to a Bloomberg report.

It really is troublesome, given the ongoing Russia probe, to have a president so tied to a hostile foreign government in his civilian life.

Seriously. There are no billionaires in Spain or Australia he could sell to?

“The primary thing I did with Russia, I bought a house in Palm Beach at a bankruptcy … I bought it for about $40 million,” he said in an ABC interview. “I sold it for $100 million to a Russian,” Trump said. “And that was primarily it.”

Trump claims that’s about the only business he’s done with a Russian.

Nobody remind him of Felix Sater and the Bayrock Group.