The sale price of a house has little to do with labour. It's mostly about the number of humans competing to live in an area vs. how easy it is to get land in that area so that a new house can be built. I.e. the ratio of how many humans are involved vs the most limiting resource for producing the thing in question.

There is the point that how wealthy the competing humans are is also a major factor. But you're trying to bypass an argument about resource scarcity by pretending that resources aren't scarce. If you follow that path to its logical conclusion you're probably going to end up in a very confusing world because then it won't make sense why everyone doesn't just get a house (if someone can't afford a house, why not just upskill and learn how to build one? It isn't that hard and there are a lot of people who don't own a house but really want one and are more than happy to work for the privilege).