You have to know that the clubs in Shanghai are different to clubs in europe or USA. Only if they based on western customer, they will offer a similar structure. Clubs that are faced to chinese guests will have a different structure. Chinese normaly will only visit a location like that in a group with boys and girls. Than most time one of the guys want to show, that he is rich, so he will invite the friends for the whole night, they will drink bottles of whiskey, vodka or other strong drinks and the whole group will get drunken fast. Nearly every club will charge a minimum spending of more than 150 $ each table, so a single guest can only sit down on the bar, most time not on a sofa place or a table. Some of the clubs also employee girls to drink with the customers for a sitting fee, some even available for take out later. Most people also don`t dance, but in a lot of clubs they will have very good DJs and also the dance-show of the "club girls" is often worth to visit this places.
Dance clubs in Shanghai often provide a huge selection of hot sexy "club girls" which are available for sit and party with you. They will charge around 300 to 700 RMB for that - depends on the club -, most are students or "part timer", some are even available to finish the party with you in your private room later (but you should clear that in advanced, best with the manager, so that he will provide girls who are available for that "additional" service). Additional to the sitting fee, take out should be around 2000 for short time and not less than 3000 for overnight, but could be even more.
This girls are definitly more expensive than KTV girls in Shanghai, but could also be more fun, because they are not really "working girls", more "party girls", so you can get a much better girlfriend experience often, also because they often students, so you will have a higher chance to get in touch with a girl who can communicate with a higher english level.