Hi CHENCE, welcome to Cruise-Chat! Congratulations on your up-coming cruise! The standard charges are 15% added to your beverages that are not free. These are all alcoholic beverages, sodas, and some juices. There will be some juice, tea, coffee, water, and a punch available free of charge in the buffet area and drink stations. The 18% charge would be included on spa treatments or the beauty salon. Tips (service fees) are added to your bill at a rate of $12/per day. You can adjust them, if you desire. We normally leave our auto-tips on the bill and then give extra to those that have gone out of their way for us. Normally for, this is the cabin steward, bar tenders, dining room waiters, and casino host. Sometimes, we'll tip the maitre d' if they've made us feel welcome. The $12/pp per day charge is divided between the cabin steward and your waiters. Room service is not included in this and we normally tips $2-$5 depending on what we've ordered.
Hope this helps.