The fundamental problem is that the value of land is inexorably tied up in the things people do with the land to actually earn money. Vacant land has little value in that sense until it's improved. You can't separate the land value from the investment in the improvements made that actually generate income. It's not quite that simple because a vacant lot in a trendy area has more potential value than a lot in a run-down area. But only because of the improvements on other nearby properties. That's what makes the land valuable -- not anything intrinsic about the land itself.