How much will a planet cost?

Could you please elaborate on the notion of "buying a planet" and what factors might influence the potential cost? Is this a hypothetical scenario or is there a real market for celestial bodies? And if there is, how would one even go about acquiring a planet, and what metrics would be used to determine its value? Are we considering the resources it may contain, its potential for habitability, or perhaps its location in the galaxy? Understanding these details would help clarify the question and provide a more accurate response.