The targeted sanctions by the EU, UK and US - in spite of being laughed at initially - are having a huge impact, I understand. These oligarch mates of his control much of the economy and typically come from the same mould and in some cases the same organisation (KGB/FSB/SVR).
The worry is he could attempt to reverse (perceived) falling popular support by attempting to annex more errant parts of the Soviet Union. One thing that struck me there, albeit several years ago, was their preoccupation with Strategic (ie nuclear) studies and the constant calculus of nuclear parity - something we've 'moved on' from in the West.
Anyway, who'd want to invest in Russia?