How much do Greyhound bus fares normally cost?

You actually don't need to use Greyhound to get to Modesto from Oakland. The public transit system goes there! All you have to do is ride BART to the Dublin station and connect with the Modesto MAX Bart express buses there. The cost round trip from BART to Modesto is $16 Good Luck! If you want to spend a little more, consider taking an Amtrak train direct between Oakland & Modesto as an alternative or on weekends or nights when the MAX bus isn't running.