You'll Never Believe How Much Robert Mueller's Russia Probe Has Cost On Tuesday, the Justice Department released a report, detailing the first four-and-a-half-months of Special counsel Robert Mueller's Russia probe. So far, the probe has cost a total of $3.2 million, including $1.7 million for salaries and benefits. More money was then spent on hiring new peoples ($500,696) and equipment for the investigation ($733,969). The remaining money was spent on travelrelocation fees, contractual services, information technology and building services. The report only details expenditures from the middle of May, when Mueller was appointed, through September.