So if you have house A that you live in, whose tax bill is $10K, and house B that's empty, whose tax bill is $7K, then your total tax should be $17K.
If you additionally have house C that is also empty, whose tax bill is $8K, then your total tax should be $10K + ($7K + $8K) x 2 = $40K.
If you additionally have house D that is also empty, whose tax bill is $5K, then your total tax should be $10K + ($7K + $8K + $5K) x 3 = $70K.
This would strongly incentivize against this activity of having one person or entity simply hoovering up homes and treating them like bars of gold.
So if you have house A that you live in, whose tax bill is $10K, and house B that's empty, whose tax bill is $7K, then your total tax should be $17K.
If you additionally have house C that is also empty, whose tax bill is $8K, then your total tax should be $10K + ($7K + $8K) x 2 = $40K.
If you additionally have house D that is also empty, whose tax bill is $5K, then your total tax should be $10K + ($7K + $8K + $5K) x 3 = $70K.
This would strongly incentivize against this activity of having one person or entity simply hoovering up homes and treating them like bars of gold.