If you are of age you can rent a room and have a party.
Be aware that you will be charged for damages.
As to the charges per person I am sure if you have the $$$$ to get a penthouse suite you don't have to worry about that.
Yes of course.
Yes.
i won't invite too much people and i think i'll only let a few stay the night with me. do penthouses charge per person or just per night?