The most fundamental right, upon which all other rights are based, is the right to life.
From the right to life derives the right to activities to maintain life. From the right to life derives the right to voluntarily trade for the goods (tools, food, clothing, real estate, etc.) necessary to maintain life. From the right to life derives the right to voluntarily trade for the goods that make life worth living, and real estate is also among those goods.
In such manner (with considerably more detail required) is the right to land ownership demonstrated. It is not just "convenient", it is a necessary component of the right to life most places on earth.
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Social Contract, on the other hand, is a problem to discuss. First, it's not a contract, which (among its other properties) is a voluntary agreement, and there's nothing voluntary about something imposed on a person at birth. Second, the "social contract" isn't the same everywhere, and the social contract of North Korea requires the murder of Christians. --- Too often, "social contract" is a verbal fog that sneaks in hidden restrictions against the life of an insufficiently careful thinker.