It's interesting to note that the average three bedroom house here in my city is about $500,000, but that's the entire thing, not just the site value (SV). That means that a person with a single investment property (over and above their primary residence) would avoid land tax as the SV might only be $300,000-$400,000. Of course there's many factors to that also like age and size of house. On the one I just moved out of the SV makes up about 60% of the total value.
With land tax here multiple property owners almost always have to pay it and as it's aggregated it ramps up there pretty quickly. The most I ever had at one time was 5 investment properties and my land tax bill was pretty sizable. Like I said, they want to tax those who they feel can afford it but I was an average Australian, hard working and I went without a lot to have those investments. I wasn't rich. So I disposed of them and realigned.