Prairie 650 help. i tokk the atv out o few days ago. parked it for the night and went to ride it the next morning and it wouldnt start. it would turn over but not enough to start it. my uncle thinks its the timing chain. what problems would this cause if teh timiing chain came off?, or could it be something else?

PRARIE650 i HAVE A 2003 Kawaski Prairie 650. i Was riding it a couple days ago, then parked it for the night. went out the next morning to ride it and it wouldnt start. the motor seemed to turn over but not enough to run. my uncle thinks the timing chain came off. what kind of damage would this cause and how much to fix. dad is taking to mechanic who charges 45 an hour. or could the problem be something else?