Good morning. I might be wrong, but my gut feeling is that the post isn't about valuation but about verbiage. I experienced a property with IDENTICAL physical improvements. Of course Nothing identical existed even in a neighborhood with 40% multi-unit improvements. The report was submitted and I devoted an extra week addressing lender/client conditions for me to describe the property as a Triplex rather than as a duplex with a legal ADU. I interviewed EVERY SINGLE SOURCE of info: city, county, textbooks, Forum, everything. {So then the big boss of the Planning Department throws a curveball by telling that a Triplex has to be in one building, adding an interesting nuance that described the frequent difference of opinions between appraiser and rest-of-the-world.} Nevertheless I eventually caved by terming the improvements as Triplex [with a hefty description of the controversy] because I couldn't find even one tangible source of info, written or verbal, that actually defined a Triplex in a functional context that addressed the Condition. I figured that if the definition was as vague as it seems, I could do no wrong by complying with the client condition.