I wouldn't know the specifics either to be honest but nearly all the dedicated Russia watchers I know espouse this approach. Bill Browder, who would know this better than anyone I assume, has made it his mission to push this message in the media all the time. And that's why Putin wants him dead. Putin and his pet oligarchs operate more like a transnational crime syndicate anyway so it is no surprise that money is their achilles heel. The UK in particular is in a pivotal position considering how much money is washed through the city of London.
As for breaking away from Putin's orbit, I doubt if you could ever extricate yourself from this world even if you wanted to. I recently saw a video of Putin humiliating Deripaska in some meeting or other. I'm not sure what it was about but where the power balance lay was obvious. In terms of sanctions against the oligarchs, the idea being pushed is that to hit one of them would do little to influence things but if enough of them are sanctioned then this may give him pause. Putin's money sits in their bank accounts too supposedly.
Go after their money, their freedom to travel, their property, and their lifestyle.
