TIMING CHAIN 96 CAVALIER REPAIR COST AND QUESTION

What is your question?

QUESTION: My son's Cavalier ran fine until he let it run out of gas.. Hwever, whn put gas in it, it did after several attmpts, crank and drove back into our driveway. After a couple of snow days, car would not turn over again. New mechanic state, it's timing and can be expensive because timing is located inside motor?? What are the repair cost and should I get a second opinion ??