You have to explain - it wont start. Wont even make a noise? or it just makes that grinding noise and never catches. Could be the battery, or the alternator, or the timing belt or the starter itself.
Probably around 20,000+ but that really depends on your area, what all it has in it etc. Could pay a little more if it has good wheels, rims, 4 wheel drive? Leather interior? power everything? All that makes a big difference.