That is a great question and I think Wenceslao gave a great answer. Additionally, you may wish to double check with a real estate attorney. I can recommend Alfredo Garcia Menocal who has an office next to my office and also owns a title company - 305.863.1000
or, my father, who is also a real estate attorney (in Sebring, FL) 863-385-5188.
My understanding is that Real Estate of four units and under qualify. 5 units and larger are considered commercial and would not qualify. For more information, follow this link to the Property Appraiser's office page explaining how to apply, etc.