Extended warranties do not cover routine maintenance like timing belt changes (just as new car warranties do not) and will not cover damage to the engine if the timing belt is not changed on schedule. This is a tough situation, I know. You can look at independent mechanics for lower prices since most of the cost is labor anyway. Just be sure to get references and understand there is not likely to be much recourse if it goes wrong.
You don't mention the model or year, or the engine, but since it has 90K miles on it I assume it is either the 3.0L or 3.3L V6, like in the Camrys through 2006, or possibly the 3.5L as in the 2007+ Camry. Of course, if it has a 4 cylinder engine I doubt your engine has a timing belt. Toyota has not used a timing belt driven 4 cylinder since the late 1980s.
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