2Fam Buildings Taxed as 3- & even 4-Fams for for Decades (NY)

[Jonn Vidal]

Why is it that so many R4-1 zones (which allow only 1-2 fam bldgs) now advertise 3Fam buildings for sale in them?

and conversely,

so many 2Fams have been taxed for decades as 3 and even 4 fams when you check the tax rolls; even says 3 or 4 units on the the notices of value despite being a 2Fam in 2 Fam zone?

been noticing this alot with NYC properties, but they arent my forte