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Welcome to Italy!But seriously though is this a second home? If so then the tax will be substantially more than if it is your primary abode.The government want to squeeze as much money out of second home owners as they can.A trip to the comune is required to find out more about the taxable status of your property. Good luck.

If you were resident then yes you would have increased costs - you would not have to pay IMU on your first house and one accessory - so a house and a store/garage, which would leave you paying IMU on the other two particelle you own.  However as a second home owner you would pay IMU and TASI on the lot, and its probabably cheaper paying bits as opposed to one lump sum, as your house would be reaccatasto as a single dwelling with a subsequent, and noteable, rise in the rateable value.   If you are doing restoration work you may well be required to reaccatasto the property after the work.   If you dont have to, then don't until the law requires you to do so.   All of this depends on the rates of IMU/Tasi and TARI that your comune levies.  If they decide that a commercial premises must pay commercial TARI (even though you are not a business, then you may find a saving, but its doubtful.  It depends on your comune.