I don't know what "beverages and more" is, but I just got back in November and liquor was $20 for Bacardi rum, Absolute, Coconut Rum, and Captain Morgan....all were 1 liter bottles and it was $80 thru room service....there is not a gratuity added. Call Princess and ask them what it is you are looking for if you are concerned they won't have it.
To Jillho.....yes, sodas are extra....as mentioned before, you can by a soda card for $22.50 plus 15% gratuity. Yes bottled water will cost you, water on the ship tastes fine....no charge at the bar for a glass of ice water. No matter if you have a soda card or not, you can not use it for room service is my understanding.
If you want a soda in the dining room, just show your waiter your cruise card as this has the sticker on it showing you have the unlimited soda card, or order a soda for $1.50/can. The soda card is only for fountain drinks too...not cans.