total cost of ownership

[Minarets1]

obviously these beasts can be modded through the roof, but what i mean, or what i am asking, i guess so i can be as informed and i can be, is maint. costs and the like...

tires: of course at 32'' (from the factory) replacing those will be pricey.
oil changes: do you have to get those done at a Hummer dealership? do they rape you? is it a somewhat standard price to pay, or is it like $100+?
brakes: do these use some ungodly type of brake?


feel free to mention or add anything else that is part of "the usuals"


again, obviously, i am not looking at comparring this to a Honda civic, i know i am buying a Hummer....but this is for my wife as a grocery getter basically. hate me if you will, im no enthusiast, but she likes it and wants one and i feel safe putting her and my 2 year old in it.

thanks for any help....again, great site!