There are nightclubs, clubs, bars in Hong Kong. Many are very expensive drinking / entertainment places but they are not to be confused with hostess clubs, where you have one to one company, and you can at least take out some of them.
The term Japanese style hostess club don't mean much because it's the main stream. Mami brings a girl to your "table", corner or private room for company. Her time is charged in one to five minute intervals. In more traditional clubs, the popular girls may have to leave you and entertain other clients if requested. I think China style means the tables are arranged as in a restaurant, with less privacy, and there is a stage for shows. Whatever style, big clubs may have promotional shows on occasions, or permanently. Karaoke clubs guarantee that you have a private room, and of course a Karaoke machine, though your choices are limited to Céline Dion, Whitney Houston, etc.
Recommendations is a mine-field in Hong Kong. The situation is volatile and good teams may switch to other clubs all of a sudden. Be careful of discussion boards. Most report of clubs are disguised promotions by insiders. But it is safe if you pick one at random. At most if they are desperate and closing, they may not honor their promotional prices published somewhere. Just ask first and have at least a few hundred to a thousand in your pocket and you will be fine. Whereas in Macau, it's so easy that there are newspaper columns dedicated to field work. The choice is down to which Japanese porn star lookalike they have in stock.
Price starts at $300 an hour in HK, to some $1500 for two hours. It's more like $500/hr in Macau. To take one out, you multiply the hourly rate by 3, and times 1.5 to 2, plus other bits and pieces that can add up. There could be minimum cover on drinks.
In big clubs as in Macau, first you have a lineup, then you pick one for a 15 min introduction. In Hong Kong mami just send you one, but you can refuse right away. After 15 min, mami will come in, and your hostess will get out. You can have another girl for another introduction, or you can bring the girl back and start the clock. The introduction time are charged somewhat higher than the normal quoted rate.
There are 3 independent departments to compete for your dollars. The "restaurant" people always want you to drink as much as possible. Time keeping wants you to stay as long as possible, offering somebody to go out and buy you dinner. The girls, who will go out with you, want to protect your pocket from others, then to take them out as long as possible.
There are always simple package deals that include everything, typically in happy hours from about 1pm to 9pm, and on the HK Island side offered by some tourist and expat friendly setups. (Some clubs start 10 am.)
Now you get the girl. If she immediately takes you somewhere else to do something, you are in luck, and you are not in a hostess club. Usually you spend an hour to the whole evening, though I don't aware there's any minimum time. If you want the option of taking her out, you better tell the mami beforehand. In clubs with local girls (HK Chinese), a significant number do not go out, and they are the better looking ones. Intimacy depends on individual girls. You may get some hand holding if she thinks you may come back for a drink. Other girls will try to do everything to lure you out, taking them with you.
For some Karaoke clubs you have the option of doing it inside, which is illegal. But if you spend a couple of hours, management will turn a blind eye. There are VIP rooms with on-suite restrooms. You can hold a German FKK type orgy party if the girls are willing.
It's not cheap. One hour inside, one hour outside, and about the same amount to the girl for her service. Usually one hour isn't very respectable. 1.5 to 2 hours are more common. So it's can easily be six times the hourly rate. But in good clubs, girls seldom return after they go out. If you take a girl out of circulation for a couple of hours after 9 pm, she won't miss much even if she returns at the small hours. Regulars will call first to check if their favorites are free.