@Brad Morsberger Request a zoning letter from the city. This will, at the very least, confirm the zoning in place. It may be that it has already been re-zoned to allow three units, and the public sources available don't reflect that yet.
In my locality, the zoning letter also states that as far as the city knows, there are no zoning violations. Doesn't mean they can't come after you later if there are, but it is good to know that as far as they are concerned, everything is fine. See section c of a portion of a zoning letter below...
Ladies and Gentlemen:
At the request of xxxxxxxxxx, we have examined our records with respect to that certain real property with all improvements thereon, lying in the City of Richmond, Virginia and identified in the City of Richmond’s real estate assessment records as Tax Map: xxxxxxxxxx, commonly known as xxxxxxxxxx (the “Property”), and we are pleased to advise you that:
a. The Property is currently zoned R-63 Residential (Multi-Family Urban) under the Zoning Ordinance of the City of Richmond, Virginia. The R-63 zoning district permits the current use of the Property as multi-family residential, as a matter of right, without the necessity of obtaining a conditional or special use permit, variance, special exception or other authorization or approval.
b. The Property is/is not subject to any proffered conditions, plan of development, use permit or other special limitations imposed by the City of Richmond, Virginia in connection with the zoning or rezoning of the Property.
c. To the best of my knowledge, the Property is currently in compliance with all applicable requirements of the zoning ordinance of the City of Richmond, Virginia. A review of our files found (i) no violations or alleged violations or regulations applicable to the Property, whether pending, contemplated or having already occurred, (ii) no fees due or pending with respect to any matter before the City Zoning Office; and (iii) no pending application for rezoning of the Property, or for a special or conditional use permit or variance in connection with the Property. Further, no proceeding to challenge the zoning or other governmental approval or use of the Property is pending, or, to the best of our knowledge, overtly threatened.