The cost of opening can vary widely depending on a number of factors, such as the location, size of the facility, type of wind tunnel, and level of customization and equipment required. However, here are some rough estimates to give you an idea. The cost of the wind tunnel itself can range from $2 million to $4 million or more. The cost of the building or facility will also depend on the location, size, and condition of the property and any renovations or modifications that need to be made to accommodate the wind tunnel. Other costs to consider include permits, licenses, insurance, marketing and advertising, staff salaries, and equipment such as harnesses, helmets, and flight suits. Overall, the total cost of opening an indoor skydiving club can range from several hundred thousand dollars to several million dollars, depending on the project's specific details.