Let us take as a base an inexpensive 9.5 m² NPW sold for 223 euros (1 euro = $ 1.21).
As even a flexible wing suffers a mass penalty (less than that of a rigid wing but not negligible) as its surface increases, we will still remain optimistic by evaluating the m² at 20 euros.
Knowing that in yo-yo mode you need about 3500 m² of wing (s) for 1 MW with a wind speed of 10 m / s (including the cosine penalty and the division by 2 because of the reel-in phase), the expense is 70,000 euros per wing (s).
By being very optimistic, the production lifespan would be 1 year, or 8760 hours, knowing that the most resistant sails reach 2000 or 3000 hours of service.
Over 20 years, we therefore expect an expenditure of 1,400,000 euros, or $ 1,694,000.
That is about the price of a complete 1 MW wind turbine.
This gives an idea of the way to go, the other elements not even being taken into account in this rough calculation.