hey man,
i used to have a 92 es300.
stay away from 92-94. they have big problems with over heating.
es300's are bad about instrument cluster lights going bad.
suspension bottoming out.
check all of those things. pour water over the suroof and watch it from inside carefully. check heater/ ac on all diffrent speeds, as the control fails alot. abs pump, and also even if your check engine light is not on, go to advance auto or somewhere like that, and do a diagnostic on it , to make sure that the light is not on, b/c some people will take the cluster out, remove the bulb, and thatway, the new owner will hnever see the light. check the valve covers, and feel the steering, on sharp turns, rack pinions are very expensive on those, and they usually leak. look at your cv boots, and also if you go to see one, dont allow them to turn the car on before you get there, that will give the car time to warm up, and by then you wont hear any knocking from the engine, once its wormed up.
hope that helped man.
good luck.