when should the timing belt be changed or inspected

The 4 cylinder Camrys have had timing chains since 2002... In 2007 Toyota started using timing chains in the V/6 engines also!!.. Your engine, whether or not it is the 2.4...2.5. 4 cylinder or the 3.5 V/6 has a timing 'chain' not a belt!!!.. There is no secluded timing 'chain' replacement !!!

04-2010 3.0 v6 with timing belt the book recommends 90,000 miles after 2010 i think they went to a timing chain