Payment for Final Fantasy XI on X360

Final Fantasy XI online is the best game ever. I have been using my computer to play this game up until a month ago and then my parents decided that I am no worst than other kids and bought me XBOX 360. Now, I have some questions for you guys that are playing on X360. Payment for Final Fantasy XI on X360 is one of the questions.

I think that it goes the same for everybody and it doesnt matter if you use PC, PS, PS2 or XBOX 360. If you buy a retail copy of the game you have one free month and the same goes if you have a way of getting a buddypass. I am still using my buddypass and I dont know how much I will have to pay when this magical thing expires, but I think it is not much because my friend has an account for more then a year and he behaves like he has snake in his wallet. It is not more then $20, I would say. And for a game like this, that is not much.