As I've mentioned before, the early titles in Mel Starr's Hugh de Singleton series tend to go/be on sale fairly often, but not so much for the later ones. Now the twelfth and next-to-most-recent in series (2019),
Without a Trace, has dropped to $2.99/£2.19 in the US/UK respectively.
Note that if you want to try the series, the first three are on sale in the US and UK right now too ($1.99 in the US, £1.46 in the UK).
Links are to the series webpages, the blurb is just for
Without a Trace.
Kindle US:
https://www.amazon.com/gp/product/B0...kindle_edition
Kindle US/Smile:
https://smile.amazon.com/gp/product/...kindle_edition
Kobo US (discountable):
https://www.kobo.com/us/en/search?qu...8-e7adffe272fc
Kindle UK:
https://www.amazon.co.uk/gp/product/...kindle_edition
Kindle UK/Smile:
https://smile.amazon.co.uk/gp/produc...kindle_edition