Sarah Jessica Parker and Matthew Broderick — as well as jewelry designer Alex Bittar — were some of the celebs who recently toured 105 Eighth Ave., a Park Slope limestone mansion that just sold to a mystery buyer for $9.5 million, far from its original $25 million asking price in 2012.

At 50 feet wide, the Tracy Mansion, as it is known, is a grand neo-classical structure, and has only had three owners since it was built in 1912.

The listing brokers were Halstead’s Jackie Lew and Marc Wisotsky.