With unprecedented speed, NYC has sent me my grandparents' marriage license from 1906. It's some help with genealogy but has less detail than I'd hoped.
I didn't know where Isaac Birk/Berk lived at that time, and now I do. Below is a photo--the tenement is still in existence, although the storefronts have obviously been updated (not necessarily "improved") since Grandpa's time.
PS Here's where my Grandma lived at the time, another address I never knew (here we are between the US Census years, so they may have moved every year for all I know). Another tenement still standing but with changed storefronts.