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 travel/relocation fees, contractual services, information technology and building services. The report only details expenditures from the middle of May, when Mueller was appointed, through September.