When you purchase a new car you would make a Shehechiyanu. Would you also make a Shehechiyanu if you leased a new car?
This is just my own logic:
Someone who builds or buys a house says shehecheyanu. It was also common to rent houses (long term as well), but the halacha did not extend to that case. So even though owning one's own house gives simcha, a limited usage doesn't qualify for the bracha.
Another interesting take on your question would be a life estate or term interest, where a person is granted usage of a property for his entire life or for a definite term, but the grantors predetermined its final owners after that time.