Treatment of property which is let to two or more persons in separate occupancies

Where any building constructed or adapted for the purpose of a single dwelling, or constructed or adapted for that purpose as two parts and for another purpose as to the rest, is let out to two or more tenants severally, the assessing authority in preparing, or revising the assessment list, or amending a current assessment list may, if it thinks fit, having regard to all the circumstances of the case, including the extent, if any, to which the parts separately occupied have been severed by structural alteration, treat the building or part thereof as a single property, and a building or part of a building so treated as a single property shall for the purposes of the property taxes, be deemed to be a single property.