Eldar Gadzhiev’s heart sank when he heard the sputtering from the engine of his Skoda one day in April. Gadzhiev, who owns a fleet of four cars that he leases as taxicabs in Moscow, knew it was a terrible and expensive time for a breakdown. Prices for spare parts, if you even could find them, had spiralled out of control since Vladimir Putin ordered the invasion of Ukraine two months earlier. “I understood that I was in a bad situation,” he said. “I thought: the repairs are going to cost as much as the car.” Dealerships were useless, he said....