Helicopters in the Everest region are mainly used for medical emergenices for trekkers, transportation of heavy goods and Everest flights.
Helicpoter flights are a lot more expensive than plane flights to see Everest with prices starting at $1000 for a 1 hour tour going up to $10,000! They are easier to take photographs from though!
Amuch cheaper option at about $150 is to take a twin otter plane flight. For more on Everest flights check out my guide to Everest viewing flights.