The property used for Dr. Allenby's home also was used in the pilot of Moonlighting (1985) as the home of Madelyn Hayes.
The approximately $400 that Dr. Allenby tells Columbo she paid for her bag would equate to around $1000 in 2023.
Columbo has numerous tie-ins to Hill Street Blues (1981) actors throughout the show's run. In this episode there is: Lindsay Crouse (Kate Harper, patrolman), Peter Jurasik (Sid the snitch), Stephen Macht (detective Phil Dugan), and multiple appearances by Ken Lerner, all as minor characters. Writer/Producer Steven Bochco had strong ties to both Hill Street and to Columbo (1971).
(at around 12 mins) When Dr. Joan Allenby walks through the party and bumps into the lady, the song playing in the background is "Deutschland-Lied", the German national anthem, played slowly.