it is a very small place , very limited exhibits, it is not a museum , not worth the money
we visited this place 6/20/18. You walked thru narrow nasty ally and stairs with almost no exhibit. All they got is some video and fun staff. We walked through it in 10 minutes. Besides, the place looked messy and disorganized , it is just a make shift place. Not worth the money at all.
The museum was really compact. It did, however, gave interesting view points of the life in red light district. Things like regulations, cost of renting a window, practices, etc. I spent roughly 30 minutes there, so it may feel like the content falls short of the 9 USD entrance ticket.
Also,the line is not long so skip-the-line ticket really doesn't mean much. Though to be fair to viator, it will cost just about as much if you show up and purchase the ticket from the museum itself.