The Trotters' Van

... is often described as a Reliant Robin, but this is not correct. The Robin was introduced in 1973; the Trotters used an earlier model, known as the Regal.

According to Wikipedia, the van used in Series 1 and most of Series 2 was a 1969 model. Wikipedia is vague about the second van that was used, but states that "all other Reliants [i.e., presumably, other than the first two] used in the TV series were the 1972 or 1973 Supervan III". The Supervan, again according to Wikipedia, is a post–1962 van and/or estate version of the Regal, with a side–hinged rear door (as can be seen in Only Fools and Horses).

© Haydn Thompson 2022