Permit variance of the front yard, side yard, rear yard, lot width, lot depth, coverage, minimum setback standards, off-street parking, or off-street loading regulations where the literal enforcement of the provisions of this chapter would result in an unnecessary hardship, and where the variance is necessary to permit a specific parcel of land which differs from other parcels of land in the same district by being of such a restricted area, shape, or slope that it cannot be developed in a manner commensurate with the development permitted upon other parcels of land in the same district. A modification of the standard established by this chapter shall not be granted to relieve a self-created or personal hardship, nor for financial reason only, nor shall a modification be granted to permit any person a privilege in developing a parcel of land not permitted by this chapter to other parcels of land in the district.