The blue hole trip is $250. us and includes the 40 us park fee and 10% sales tax. its been the same price for years and i don't hear any of the operators planning to change it.
It takes 2 to 2 and one half hours to get there and the same back.
i send the trip out about three times a week.

White Sands Dive Shop
https://whitesandsdiveshop.com/