I think this comes down to correlation versus causation. The fact that someone (perhaps yourself) valued a property highly recently is correlated with that pro

I think this comes down to correlation versus causation. The fact that someone (perhaps yourself) valued a property highly recently is correlated with that property having a high present value. But it does not cause it. It is possible the million dollar purchase was a mistake, or that something has changed and it's now worth far less. Valuing a property highly may cause you to have paid a lot of money for it, and that might be a reason to assess the current value highly. But that's very, very different from valuing a properly highly because you paid a lot of money for it.