Partial interest valuation & Fractional Interest
Often, the ownership of residential or commercial real estate isn't cut and dried. One might own a property outright, by himself, unencumbered by liens or mortgages, leases or easements. But he/she might also own it as a "joint tenant" with his wife, Mrs. Jones. The Jones' may lease some of the property to another party.
They may have signed an agreement to give up any subsurface or mineral rights they have in the property in exchange for cash. There may be a restriction in the deed stipulating that the residential or commercial real estate must never contain a structure more than two stories in height. There are many ways that the full bundle of rights in real estate might be distributed.