Radiator leak/Replace radiator on Chrysler LHS 2001 with 101000 miles?
 

Ok I dropped off my car at a local shop in Salt lake city, Utah for a timing belt job. After a couple of hours, they called me and said that they found a huge amount of leak in the radiator and it needs to be replaced right away. Since I didn't have time to get a second opinion from an other mechanic, I asked them to proceed with that. I was charged $750 at the end. This is all they did: Replaced the radiator with a new one, put new upper and lower hoses, drained and filled the coolant (I was told by a few people afterwards that they should have flushed the coolant rather than drain and fill), evacuated, recharged the ac system. I keep thinking about this and wasn't sure if I was cheated. Can anyone please let me know whatever they did is right? Or did they miss something? Or they overcharged me? Is that the radiator that caused the leak or could the leak be from somewhere else? I would really appreciate if I could get answers for all of my questions. Thanks for your time.