Phipps Houses, one of the city’s most storied affordable housing development firms, is putting its 894-unit Kips Bay Court complex on the market, several sources told The Real Deal. The majority of the units in the group of eight buildings located between 26th and 29th streets east of Second Avenue are occupied by free market tenants. Studio apartments start at $2,711 and three-bedroom units start at $6,426, according to the complex’s website.