It depends. When I started, I would spend $24 for a McCall's pattern at JAF with a coupon. I am boycotting McCall's these days, but I don't regret spending that amount of money for my first quilts. It had detailed instructions, paper patterns & lots of tips. It was basically like a class on quilt construction. Between that & the JAF BOM's where you got all the pieces pre-cut, along with the instructions about how to piece them together into blocks & rows, I was able to learn the basics of quilting enough to be able to have a foundation to recognize good YouTube tutorials when I saw them.
Nowadays, I prefer to support small designers directly. I spend $12-18/pattern depending on the intricacy of the design, what all is included & how many quilts I'm allowed to make and sell based on a single copy of a pattern. I mostly do applique quilts, so I need the applique units & the sheet showing the layout. If the pattern breaks down the applique units into their individual components, that's a major bonus -- and time saver!