How much does IoT cost?

I'm curious, how much does the Internet of Things, or IoT, actually cost? It seems like a vast and complex network of interconnected devices, so I'm wondering if there's a clear-cut answer or if the cost varies widely depending on the scale and complexity of the implementation. Are there any common factors that drive up the price, and are there any cost-saving measures that can be taken? I'm eager to learn more about the financial side of IoT adoption.