How much did the Sakhalin oil and gas complex cost?

The Sakhalin oil and gas complex, particularly the Sakhalin-1 and Sakhalin-2 projects, involved significant investment costs. Sakhalin-2, for instance, had estimated costs exceeding $20 billion. Overall, the combined investment for both projects has been in the range of $40 billion or more, reflecting the complexities and scale of developing hydrocarbon resources in the region.