"Have Guns - Will Haggle" is a reworking of "Invitation To A Killing," the original story intended to introduce Tara King. It was produced by John Bryce who was originally set to take over as main producer on series 7. However, after shooting most of three episodes, Brian Clemens and Albert Fennell were asked to return. It is unclear how much material from "Invitation To A Killing" survived in the rewritten version by Clemens and Fennell.
One of the very few episodes of the series where there is a Black character.