Just checked their website, and I wasn't able to find any prices either. The only thing they mentioned was a €60 entrance fee. Have you checked their Google Reviews? Otherwise, you may need to contact them.
Coming back to your initial question, I personally would much rather spend a bit more to visit a place that I *actually* want to visit than some place that might be a bit cheaper. You're already spending a big amount of money - better make it worth it!
Good luck, have fun & stay safe :')