$125,000 — though that figure could rise if he is called before special counsel Mueller's grand jury.

The ongoing probes of Russian election meddling are roiling Washington, spawning new legal actions — and increasingly, emptying the pockets of the people involved in them. Becoming ensnared in a federal investigation into the links between Donald Trump's presidential campaign and the Kremlin can pose a serious financial threat for those involved at any level. In an interview with CNBC, former Trump campaign advisor Michael Caputo described the financial strain of being a witness in the House Intelligence Committee's investigation. "If you don't go into a congressional hearing thoroughly prepared, then you should bring a toothbrush, because you're going to be there a while," Caputo said in a phone interview. While his legal fees were cheaper in his home state of New York than they would be in Washington, Caputo still paid about $25,000 per hearing. A good chunk of that fee actually goes toward producing the required documents for investigators. For Caputo, who has known and communicated with some of the central figures in the federal probes for decades, it's a huge task. "If I have 800 emails where I mention Trump and Russia in the same email, figuring out which ones are of interest to an investigator is above my pay grade" to sift through alone, Caputo said. Caputo said he first retained attorneys in March last year, after he was named by Rep. Jackie Speier, D-Calif., in congressional testimony as being Russian President Vladimir Putin's "image consultant." He has since filed an ethics complaint against Speier, whom he called "a liar all the way to the cellular level."

Speier's office did not immediately respond to CNBC's request for comment. Caputo has only been interviewed by the House committee as a witness, meaning he is not suspected of committing any crimes. He has been tapped to testify before investigators in the Senate, however, and said he expects to be called before special counsel Robert Mueller's team in the future. His status as a mere witness is all the more reason to go in prepared through legal counsel — "even if you're telling a story about ice cream, because these are some of the most irresponsible people on earth," he said, referring to Congress. Stanley Twardy Jr., a former U.S. attorney in Connecticut, agreed that preparation is crucial, despite its expense. "You don't want to say anything false, because you could go from witness" to worse, Twardy said. Becoming a subject or a target in a case will likely exacerbate the time and money involved, he said. The process of preparing a client for multiple congressional hearings, and possibly a grand jury appearance, is time-consuming and expensive. "Hell, at my rates that's gonna be close to $100,000," Twardy said, hinting that the figure would be much higher inside the Washington beltway. All told, Caputo estimates that his legal fees will total $125,000. But that's a conservative figure, he said, adding, "If I go to the grand jury" as part of the special counsel's probe, "it'll be far more." He recently started a crowdfunding page to help pay his legal fees.

Greater costs

Being linked to a high-profile and politically charged investigation has dealt a severe blow to Caputo's career and personal life as well, he said. "It's a balancing act" between tending to the clients of his public relations firm and dealing with the requirements of the investigations, he said. "I've lost clients," he said. "It's had a dramatic effect on my business." He said his family, too, has suffered from his exposure. In an interview with conservative news site National Review Online, Caputo said his family received "constant threats of violence" for his public defense of Trump and involvement in the investigations. "Last month, my wife received a part of a sniper rifle in the mail," Caputo told the website. These threats have led to further investments in security. "I have guns in my house and in my office that I never had there before," he said. "If they're coming for me, I'm going to take them out first." Caputo has had to pay extra for security services, including cameras, in his home and office as well.

Bigger figures

Roger Stone, Trump's longtime confidant and surrogate, told CNBC that his mounting legal fees already add up to more than half a million dollars.

"To date my legal costs all pertain to the House Intelligence Inquiry, the Senate Intelligence and Judiciary Inquiries and defending against the harassment lawsuit filed by Project Democracy again me and the Trump campaign," Stone told CNBC in an email. His fees are projected to double to $1 million, he said, in light of a sweeping new lawsuit filed last week by the Democratic National Committee. The suit names more than a dozen defendants, including Stone, Wikileaks and Trump's family members, and alleges an illegal conspiracy to help Trump win the 2016 election. Stone called the lawsuit "bogus," and has said he intends to use the suit as leverage to get undisclosed records from the Democrats. But that strategy could be costly as well. Companies that use electronic programs to search for such records are sometimes more expensive than lawyers in the short term, Twardy said. "My clients have been aghast at the cost" of such services, he added. While Stone goes on the offensive, former national security advisor Michael Flynn's son, Michael Flynn Jr., recently suggested that the burden of defending against the special counsel was the real reason why his father pleaded guilty to federal crimes. Michael Flynn Jr. tweet Michael Flynn Jr. could not be reached for comment.

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