The house that Christine drives the buggy to, where her dad lives, is Norman Bates house in the movie Psycho.
The original air date of April 15, 1971 is for the Eastern and Central time zones only. The show led into an NBA basketball playoff game, which ran long and pre-empted the show in the Mountain and Pacific time zones (where it was to run after the game). Viewers in that time zone saw this show on April 29.
At the end when Oscar is complaining about how freely Alan is offering everyone his expensive brandy, he mentions it costs $22.00 a bottle. That would have been about the price of an ounce of gold then, which now is worth about $1,750.