Making money from modeling

Hi, I'm new, I don't know roblox, but I know blender. I wonder if it's possible to make money by creating models and adding them to the market. Is there a chance that they will sell? Or maybe they have to be related to some game. And the last question: what influences the price? Why do items in the market cost 100 RBX, and very similar ones in the creator are free? Regards