An Nisaa means "women' in Arabic, so you can guess that this hairdressing salon is just for women. Strictly no men allowed inside because this salon caters to the needs of Muslim women who veil themselves and do not let non-male relatives see their hair. That's why these women don't patronise your regular neighbourhood hairdreser.
I've been to this salon once as a teen. The salon was empty so I sat down and waited. It turned out that the hairdresser was performing her prayers at the back of the salon. I told her I wanted to get my hair dyed with henna and she promptly picked a suitable red hue for me. As she dyed my hair, she also gave me tips on how to manage my fussy scalp. I don't remember how much I paid for her service though, but she's a very nice, chatty lady and I felt simply at ease with her.