The timing belt was due at 90K miles (first source) but it is common practice for sellers not to replace the belt before selling. It is very hard to recoup the cost of timing belt replacement from buyers. Belt replacement, without the recommended water pump and crank/cam seals, is roughly $300-$500 for your Solara (second source - put your zip code in for a better estimate). A proper job, with water pump and seals, adds about $200 to your cost and will add nothing to the selling price.
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