What else should you do when you replace a timing belt

You have to take off drive belts for access and they are made of rubber too. Replace them if same age as timing belt. Water pump is driven by timing belt and will not last till next time timing belt is due so replace it when exposed during disassembly. Seals should be done for same reason unless they are already starting to seep/leak when in there so at that point it is obvious. Also, check the tensioner and idler pulleys for replacement while in there. So much of this is exposed when doing timing belt so makes sense to replace while in there unless you like to do repeated teardowns.