A robot vacuum costs thousands of dollars (will about a thousand) and they don't work very. There is no way that you are going to get a machine that is orders of magnitude more complex down to that price point any time soon.

A business case is not just a matter of a willing buyer. It is a buyer and a vendor who can agree on a price that works for both. You may have agreed but the physics of the matter mean that there is nobody to take the other side.