lol, no worries - so many people ask because it is a difficult thing to work out! I think we can discuss techniques just not prices. You can always pretend to be a customer and ask local businesses what they charge 🙂
It is MUCH better to charge per project than per hour simply because you will earn more if you do it correctly. Don't charge less than you are worth. A few K-time bars is what you want to charge, minus the -time bars 😉
It all depends!