Thing is, no project is the same and every client differs. A designer can’t give an accurate quote until a design brief is in place, and that doesn’t happen until after talking.
This design pricing formula does a little to explain the complexity of cost.
To learn about pricing from other designers, get the “Pricing your work” chapter from Work for Money, Design for Love when you join the mailing list. Or if you’d rather not give your email, here are some relevant resources on pricing your skills.
A few thoughts on pricing.