What parts should i change in order to completely do a timing belt change on an '01 mitsubishi galant?

I own a 2001 mitsubishi galant es, 4 cylinder, and i just reached 150,000 miles and would need to do a timing belt change asap because the vibration of the engine is increasing and the change of the belt is needed at this point. I would however like to know what are all the parts, besides the water pump, that i need to change when doing the timing belt change. Thank you for your help.
What parts should i change in order to completely do a timing belt change on an '01 mitsubishi galant?
Replace the balance shaft belt and timing belt, check the water pump weep hole for coolant leakage because if you have it that far down it would be easier to replace.

It was rare for the idler or tensoner bearings to be bad but check them for bearing roughness anyhow of course.

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