I wanna get into sculpting but it seems too expensive

I'm really new to clay, and I took a beginner ceramics class last year where we used stoneware clay and fired it in an oven. I mainly intend to sculpt human & animal figures.

I've been exploring different clays, and Sculpey so far seems great to use. It's very easy to deform and can be baked with an armature, but just a few ounces could cost 10 to 20 dollars, letting me only do small projects. Also projects feel pretty fragile after an oven bake.

What are some clays or sculpting methods that are affordable, good for making posed figures and have durable baked results?