Right, for example if I was shopping right now a house elevator would be a huge positive to me as my daughter is a wheelchair user and will be getting more difficult to carry up and down the stairs.

That said as someone who was in a lot of middle class and upper class homes due to a previous job, I saw exactly one elevator in a single family home. I doubt it would even factor into the price because most people would have no interest in even using the elevator beyond a novelty.