Mrs. Writeman, the mother of the spoiled teenager in the dealership, is played by Nancy Priddy, the real-life mother of series star Christina Applegate.
The cars featured in this episode are as follows: Al's original car is a 1973 Plymouth Duster. The car he wants to buy is a 1988 Ford Mustang. His first used car is a 1975 AMC Pacer, the second is a 1976 AMC Gremlin, and the final one (that actually works) is the 1972 Plymouth Duster that doubles as "the Mighty Dodge" for the remainder of the series.
The homeless man who gives Al money is the same actor who sells Steve back Marcy's Barbie doll in the Season 2 episode Guys and Dolls (1988) and has played that same role in several other episodes over the course of the series.