Going through the responses here, and my two cents worth.
Unless there is a visible problem with the belt and tensioner, I see no justifiable reason why the dealer would want to replace them, other than to make a quick buck (I wouldn't be surprised if they only changed the belt, and left the tensioner in there, but charged you for both). I'd give that a hard pass.
Coolant is a rip off. Just keep the overflow canister at the proper fill level, and you are good for a lot more miles on your current coolant.
Brake stuff can vary from state to state and country to country. Here in Ottawa (Canada), hourly rates are usually in the $140-150 range. Two hours per axle is the norm, so four hours labour for front and back, about $500-600, plus parts. You could buy good quality rotors and pads on line and bring them in to the dealer. The dealer parts pricing is obscene in my opinion. I don't think a brake fluid flush is mandatory either, but everyone has a different opinion on that. I'd just replace the pads and rotors and move on.