Home Made Greek Yogurt - How much yogurt can you get from 1/2 gal of milk? Worth the trouble?

Is it worth the trouble to make Greek Yogurt to save money ? Lets find out. I learnt how to make Greek yogurt off You Tube. There are plenty of tutorials out there for better instructions. Here, I just want to explore whether it is worth while to make your own vs buying it off the store shelf.