There are definitely some confounding factors other than architecture to account for. At least in Boston, new construction isn't replicating the century-old triple decker (of course, truly doing that would take a century of wear and tear). So I have to wonder how much of that price premium comes from having brand new stainless steel appliances and on-site gyms instead of creaky floors and questionable wiring. And then it seems to me, just wandering around town, the "modern" new construction is priced well above market price (lots of units sit vacant for a long time, with many eventually adding deal-sweetening offers like a month or two of free rent).