The house next door: 18-20 Jones Street (1844), Greenwich Village, New York
Despite the shared facade, 18 and 20 Jones Street are two separate houses. They were built in the Greek Revival style in 1844 and share a common wall approximately where the drain pipe runs to the left of the stoop. Both stoops were removed sometime after 1947, but the one at No. 20 was later restored. In 2010 both houses were placed on the market, generating some "preservation anxiety." The owner of No. 18 agreed to sell only if the houses were sold together, but in 2014 No. 20 was sold separately. Here is a photo from 2011 showing both houses, No. 18 "stoopless.": gvshp.org/blog/2011/04/19/18-20-jones-street/.