IBI Inconsistency

I have 2 properties on the same urbanization. One is a 2 bed apartment and the other is a an end of terrace house with garden.

The IBI on the apartment is 150 and while I would expect IBI on the house to be higher, it is 4.5 times higher at 660.

I know IBI is calculated of the Valor Cadastral but I don't understand such a huge difference. Apartment is 50 sq m and house about 100 sq on plot about 250 sq m. Both were built at the same time. I bought apartment in 2004 and house in 2007.

Speaking to neighbours with similar sized plots, their IBI is about 400. Is there any way I can investigate why the IBI on my house is so high,?

Thanks,

Sean

Square metres can make a big difference.

Also I believe some Town Halls give discounts if you are resident and on the padron etc but they don't care about residency if you register on padron becuase it means tey get more money from central funds!

But otherwise pop into Town Hall and query.

Is it possible that a 250 sq m plot occupies 4.5 times more space than a 50 sq m apartment, so the rates are 4.5 times higher?