Is chatbot free or paid?

Can you clarify for me whether chatbots are typically offered as a free service or do they come with a cost? I'm curious to understand if there's a standard pricing model in the industry, or if it varies depending on the features and functionalities offered by different chatbot platforms. Additionally, if chatbots are indeed free, what are the potential limitations or restrictions that users might encounter? And on the other hand, if they're paid, how does the pricing structure work, and what benefits do paid chatbots offer over their free counterparts?